Liquid container having liquid consumption detecting device

ABSTRACT

A liquid container, comprising: a housing containing therein liquid; a liquid supply opening formed in the housing for withdrawing the liquid from the housing; a liquid sensor mounted on the housing for detecting a level of the liquid which is variable in accordance with a consumption of the liquid; and a first partition wall extending in an interior of the housing and defining the interior of the housing into at least two liquid accommodating chambers which communicate with each other, the liquid accommodating chambers comprising: an air-communication side liquid accommodating chamber which communicates with ambient air; and a detection side liquid accommodating chamber in which the liquid sensor is disposed at an upper portion thereof.

[0001] The present patent application claims priority from Japanesepatent applications Nos. H. 11-139683 filed on May 20, 1999, H.11-147538 filed on May 27, 1999 and H. 11-256522 filed on Sep. 10, 1999,the contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a liquid container equipped witha piezoelectric apparatus therein which detects the consumption state ofliquid inside a liquid container which houses the liquid. Moreparticularly, the present invention relates to the liquid containerequipped with a piezoelectric apparatus that detects liquid consumptionstatus in a liquid container which provides liquid to a recording headof an ink-jet recording apparatus.

[0004] 2. Description of the Related Art

[0005] An ink cartridge mounted on an ink-jet type recording apparatusis taken as an example of a liquid container and is described below. Ingeneral, an ink-jet recording apparatus comprises: a carriage equippedwith an ink-jet type recording head comprised of a pressure generatingmeans which compresses a pressure generating chamber and a nozzleopening which discharges the compressed ink from a nozzle opening in theform of ink droplets; and an ink tank which houses ink supplied to therecording head through a passage, and is structured such that theprinting operation can be performed continuously. In general, the inktank is structured as a cartridge that can be detached from therecording apparatus, so that a user can easily replace it at the timewhen the ink is used up.

[0006] Conventionally, as a method of controlling the ink consumption ofthe ink cartridge, a method is known of controlling the ink consumptionby means of a calculation in which the counted number of ink dropletsdischarged by the recording head and the amount of ink sucked in amaintenance process of the printing head are integrated by software, andanother method of controlling the ink consumption in which the time atwhich the ink is actually consumed is detected by directly mounting tothe ink cartridge two electrodes for use in detecting the liquidsurface, and so forth.

[0007] However, in the calculation-based method of controlling the inkconsumption by integrating the discharged number of ink droplets and theamount of ink or the like by the software, the pressure inside the inkcartridge and the viscosity of the ink change depending on usageenvironment such as ambient temperature and humidity, elapsed time afteran ink cartridge has been opened for use, and usage frequency at a userside. Thus, a problem is caused where a considerable error occursbetween the calculated ink consumption and the actual ink consumption.Moreover, another problem is caused in which the actual amount of inkremaining is not known because once the same cartridge is removed andthen mounted again, the integrated counted value is reset.

[0008] On the other hand, in the method of controlling by electrodes thetime at which the ink is consumed, the remaining amount of ink can becontrolled with high reliability since the actual ink consumption can bedetected at one point. However, in order that the liquid surface of theink can be detected, the ink need be conductive, so suitable types ofink for use are very limited. Moreover, a problem is caused in that afluid-tight structure between the electrodes and the cartridge might becomplicated. Moreover, since precious metal is usually used as theelectrode material, which is highly conductive and erosive,manufacturing costs of the ink cartridge increases thereby. Moreover,since it is necessary to attach the two electrodes to two separatepositions of the ink cartridge, the manufacturing process increases,thus causing a problem which increases the manufacturing costs.

[0009] Moreover, when managing the ink consumption status by mounting apiezoelectric device on the ink cartridge, ink inside the ink cartridgemay roll or bubble by the scanning of the ink cartridge during theprinting operation. By the waving or bubbling of ink nearby thepiezoelectric device, ink or bubble of ink attaches to the piezoelectricdevice. Then, there is a cases arises that the piezoelectric devicecannot detect the ink consumption quantity by the ink or bubble of inkattached to the piezoelectric device. In other words, even there is onlysmall amount of ink inside the ink cartridge, if the ink attaches to thepiezoelectric device mistakenly by the waving of ink, there is a dangerthat the piezoelectric device detects mistakenly that there is stillenough ink inside the ink cartridge. Moreover, if the bubble attaches tothe piezoelectric device, there is danger that the piezoelectric devicedetects mistakenly that there is no ink inside the ink cartridge even ifthe ink cartridge 180 is filled by ink.

[0010] Furthermore, there is problem that the position of mounting thepiezoelectric device on the ink cartridge is limited for detecting theink end status inside the ink cartridge. For example, if mounting thepiezoelectric device on the wall at the lower side of the ink surface,the piezoelectric device can detect the ink end. On the other hand, ifmounting the piezoelectric device on the wall at the upper side of theink surface, the piezoelectric device cannot detect the ink end.

SUMMARY OF THE INVENTION

[0011] Therefore, it is an object of the present invention to provide aliquid container capable of reliably detecting a liquid consumptionstatus and dispensing with a complicated sealing structure.

[0012] Moreover, it is another object of the present invention toprevent the waving or bubbling of liquid around the piezoelectric deviceinside the liquid container.

[0013] Furthermore, it is still another object of the present inventionto provide a liquid container, the piezoelectric device of which canreliably detect a liquid consumption status by detecting the liquidsurface even in the case that liquid inside the liquid container rollsand bubbles.

[0014] Furthermore, it is still another object of the present inventionto provide a liquid container, the piezoelectric device of which canreliably detect a liquid consumption status even in the case that theliquid container tilts or fell down because the gas does not contactswith the piezoelectric device.

[0015] Furthermore, it is still another object of the present inventionto provide a liquid container capable of reliably detecting a liquidconsumption status in the liquid container even if the piezoelectricdevice is mounted on the upper side of the liquid surface in the liquidcontainer.

[0016] Furthermore, it is still another object of the present inventionto provide a liquid container which does not need to be mounted on theaccurate position, in other words, the mounting position of thepiezoelectric device on the liquid container can be freely designed.

[0017] These objects are achieved by combinations described in theindependent claims. The dependent claims define further advantageous andexemplary combinations of the present invention.

[0018] According to an aspect of the present invention, there isprovided a liquid container which may comprise: a housing containingtherein liquid; a liquid supply opening formed in the housing forwithdrawing the liquid from the housing; a liquid sensor mounted on thehousing for detecting a level of the liquid which is variable inaccordance with a consumption of the liquid; and a first partition wallextending in an interior of the housing and defining the interior of thehousing into at least two liquid accommodating chambers whichcommunicate with each other, the liquid accommodating chamberscomprising: an air-communication side liquid accommodating chamber whichcommunicates with ambient air; and a detection side liquid accommodatingchamber in which the liquid sensor is disposed at an upper portionthereof.

[0019] The liquid container may further comprises a porous memberaccommodated within the detection side liquid accommodating chamber. Theliquid supply opening may be formed in the air-communication side liquidaccommodating chamber. The liquid supply opening may be formed in thedetection side liquid accommodating chamber. A volume of theair-communication side liquid accommodating chamber may be differentfrom that of the detection side liquid accommodating chamber. Thevolumes of the at least two liquid accommodating chambers may decreasefrom one side wall of the housing to the other opposite wall.

[0020] The liquid container may further comprising a second partitionwall extending in the detection side liquid accommodating chamber anddefining at least two small detection chambers. The second partitionwall may be formed with a liquid communication opening at a lower partthereof. The second partition wall may be formed with a liquidcommunication opening at an upper part thereof. The detection sensor maybe disposed on each of the small detection chambers. The volumes of thesmall detection chambers may be different from each other. The volumesof the at least two small detection chambers may decrease from one sidewall of the housing to the other opposite wall.

[0021] The detection side liquid accommodating chamber may generate nocapillary force for holding the liquid. The small detection chamber maygenerate no capillary force for holding the liquid. The detection sideliquid accommodating chamber may comprise a recessed part formed at atop wall thereof. The liquid sensor may comprise a cavity which openstoward an interior of the housing for holding the liquid. The liquidsensor may comprise a piezoelectric device having a vibrating section,the vibrating section generates a counter electromotive force inaccordance with a residual vibration of the vibrating section.

[0022] The liquid sensor may detect at least an acoustic impedance ofthe liquid and detects a liquid consumption status in accordance withthe acoustic impedance. The liquid container may be mounted on anink-jet printing apparatus having a printhead which ejects ink droplets,and the liquid container supplies the liquid contained therein to theprinthead through the liquid supply opening. The volume of the detectionside liquid accommodating chamber may be equal to or less than half thevolume of the air-communication side liquid accommodating chamber. Thevolumes of the liquid accommodating chambers may decrease from one sidewall of the housing to the other opposite wall.

[0023] The porous member may comprise a first porous material disposedclose to the liquid sensor and a second porous material disposed farfrom the liquid sensor compared with the first porous material, and thesecond porous material has a higher liquid-philic characteristics thanthe first porous material. The liquid sensor may comprise apiezoelectric device having a vibrating section, the vibrating sectiongenerates a counter electromotive force in accordance with a residualvibration of the vibrating section. The liquid sensor may detect atleast an acoustic impedance of the liquid and detects a liquidconsumption status in accordance with the acoustic impedance. The liquidcontainer may be mounted on an ink-jet printing apparatus having aprinthead which ejects ink droplets, and the liquid container suppliesthe liquid contained therein to the printhead through the liquid supplyopening.

[0024] According to another aspect of the present invention, there isprovided a liquid container which may comprise: a housing containingtherein liquid; a liquid supply opening supplying liquid to an exteriorof the housing; a detection device mounted on the housing, the detectiondevice comprising a piezoelectric element for detecting a liquidconsumption status; and a wave absorbing wall extending in an interiorof the housing disposed at a place facing the detection device. A gapmay be defined between the detection device and the wave absorbing wall.The gap may not generate a capillary force for holding the liquid.

[0025] The gap may generate a capillary force which is smaller than aforce for holding the liquid. The detection device may comprise a cavityfor receiving and holding liquid, the cavity being formed to open towardthe interior of the housing. The wave absorbing wall may be secured toand extends from an interior wall of the housing. The detection devicemay be attached to a first wall of the housing which extends in avertical direction of the liquid level, and the wave absorbing wall mayextend in parallel with the first wall of the housing.

[0026] The detection device may be attached to a bottom wall of thehousing, and the wave absorbing wall may extend in parallel with theliquid level. The wave absorbing wall may extend in an inclineddirection with respect to the liquid level. The wave absorbing wall mayextend from a side wall of the housing which is perpendicular to theliquid level. The a capillary force may be generated between at least apart of the internal wall and an inner wall of the housing. The waveabsorbing wall may comprise a bending section which is formed by bendingat least a part of an edge of the wave absorbing wall toward a wall onwhich the detection device is mounted, and a gap defined by the bendingsection and the detection device generates a capillary force while a gapdefined by the wave absorbing wall and the detection device does notgenerate a capillary force.

[0027] The wave absorbing wall may comprise a plurality of waveabsorbing wall pieces, and at least one of the plurality of waveabsorbing wall pieces may extend from a side wall of the housing whichis perpendicular to the liquid level. The detection device may comprisea vibrating section which generates a counter electromotive force inaccordance with a residual vibration of the vibrating section. Theliquid container may be mounted on an ink-jet printing apparatus havinga printhead which ejects ink droplets, and the liquid container maysupply the liquid contained therein to the printhead through the liquidsupply opening.

[0028] According to the other aspect of the present invention, there isprovided a liquid container may comprise: a housing containing thereinliquid; a liquid supply opening formed in a wall of the housing forwithdrawing the liquid to an exterior; a detection device mounted on thehousing, the detection device comprising a piezoelectric element fordetecting a liquid consumption status; and a porous member disposedwithin the housing in the vicinity of the detection device. Thedetection device may contact the porous member. A gap may be definedbetween the porous member and the detection device.

[0029] The detection device may comprise a cavity and a vibratingsection which contacts the liquid through the cavity, and the porousmember is disposed in the cavity. A capillary force of the porous membermay be smaller than a force which holds the liquid. The detection devicemay comprise a base plate, a vibrating portion and a through hole formedin the base plate, and the porous member covers at least a part of thethrough hole. The detection device may further comprise a grooveconnecting with the through hole, and the porous member is disposed onthe groove. The detection device and the porous member may be disposedon a plane where the liquid supply opening is formed.

[0030] The detection device may comprise a vibrating section whichgenerates a counter electromotive force in accordance with a residualvibration of the vibrating section, and the detection device detects theliquid consumption status in accordance with the counter electromotiveforce. The detection device may comprise a piezoelectric element and amounting structure unitarily formed with the piezoelectric element, andthe mounting structure is attached to the housing. The liquid containermay be mounted on an ink-jet printing apparatus having a printhead whichejects ink droplets, and the liquid container supplies the liquidcontained therein to the printhead through the liquid supply opening.

[0031] This summary of the invention does not necessarily describe allnecessary features of the present invention. The present invention mayalso be a sub-combination of the above described features. The above andother features and advantages of the present invention will become moreapparent from the following description of embodiments taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0032]FIG. 1 shows a side cross sectional view of an embodiment of theink cartridge according to the present invention.

[0033]FIG. 2 shows a side cross sectional view of the other embodimentof the ink cartridge according to the present invention.

[0034]FIG. 3 shows a side cross sectional view of the further otherembodiment of the ink cartridge according to the present invention.

[0035]FIG. 4 shows a side cross section of the further other embodimentof the ink cartridge according to the present invention.

[0036]FIG. 5 shows a side cross section of the further other embodimentof the ink cartridge according to the present invention.

[0037]FIG. 6 shows a side cross section of the further other embodimentof the ink cartridge according to the present invention.

[0038]FIG. 7 shows a side cross section of the further other embodimentof the ink cartridge according to the present invention.

[0039]FIG. 8 shows a side cross section of the further other embodimentof the ink cartridge according to the present invention.

[0040]FIG. 9 shows a side cross section of the further other embodimentof the ink cartridge according to the present invention.

[0041]FIG. 10 shows a side cross section of the further other embodimentof the ink cartridge according to the present invention.

[0042]FIG. 11 shows a side cross section of the further other embodimentof the ink cartridge according to the present invention.

[0043]FIG. 12 shows a side cross section of the further other embodimentof the ink cartridge according to the present invention.

[0044]FIG. 13 shows a side cross section of the further other embodimentof the ink cartridge according to the present invention.

[0045]FIG. 14 is a perspective view of the ink cartridge which storesplural types of inks, viewed from a back side thereof, according to anembodiment.

[0046]FIG. 15 is a perspective view of the ink cartridge which storesplural types of inks, viewed from a back side thereof, according to anembodiment.

[0047]FIG. 16 is a perspective view of the ink cartridge which storesplural types of inks, viewed from a back side thereof, according to anembodiment.

[0048]FIG. 17 is a perspective view of the ink cartridge which storesplural types of inks, viewed from a back side thereof, according to anembodiment.

[0049]FIG. 18 is a cross sectional view showing an embodiment of a majorpart of the ink-jet recording apparatus suitable for the ink cartridgeshown in FIG. 1.

[0050]FIG. 19 is a detailed cross sectional view of a subtank unit 33 asan embodiment of the liquid container according to the presentinvention.

[0051]FIG. 20 is a cross sectional view of another embodiment of asubtank unit 33 of the liquid container according to the presentinvention.

[0052]FIG. 21 is a cross sectional view of further another embodiment ofa subtank unit 33 of the liquid container according to the presentinvention.

[0053]FIG. 22 shows a detail and equivalent circuit of an actuator 106,which is an embodiment of the piezoelectric device of the presentinvention.

[0054]FIG. 23 shows a detail and equivalent circuit of an actuator 106,which is an embodiment of the piezoelectric device of the presentinvention.

[0055]FIG. 24 is a graph which shows the relationship between the inkquantity inside the ink tank and the resonant frequency fs of the inkand the vibrating section.

[0056]FIG. 25 shows a waveform of the residual vibration of the actuator106 and the measuring method of the residual vibration.

[0057]FIG. 26 shows the manufacturing method of the actuator 106. Aplurality of the actuators 106, four numbers in the case of the FIG. 26,are formed as one body.

[0058]FIG. 27 shows a cross-section of a part of the actuator 106.

[0059]FIG. 28 shows a cross-section of the actuator 106.

[0060]FIG. 29 shows the manufacturing method of the actuator 106 shownin FIG. 26.

[0061]FIG. 30 shows the further other embodiment of the ink cartridge ofthe present invention.

[0062]FIG. 31 shows further other embodiment of the ink cartridge of thepresent invention.

[0063]FIG. 32 shows other embodiment of the through hole 1 c.

[0064]FIG. 33 is a slant view of the further other embodiment of theactuator.

[0065]FIG. 34 shows a slant view of the other embodiment of theactuator.

[0066] FIGS. 35 shows plan views of the through hole 1 c according toanother embodiment.

[0067]FIG. 36 shows a slant view of the configuration that forms theactuator 106 in one body as a mounting module 100.

[0068]FIG. 37 shows an exploded view of the module 100 shown in FIG. 36to show the structure of the module 100.

[0069]FIG. 38 shows the slant view of the other embodiments of themodule.

[0070]FIG. 39 shows an exploded view of the module 400 shown in FIG. 38to show the structure of the module 400.

[0071]FIG. 40 shows the further other embodiment of the module.

[0072]FIG. 41 shows a cross-sectional view around the bottom of thecontainer 1 when the module 100 shown in FIG. 36 is mounted on thecontainer 1.

[0073]FIG. 42 shows the cross section of the ink container when mountingmodule 700B on the container 1.

[0074]FIG. 43 shows an embodiment of an ink cartridge and an ink jetrecording apparatus which uses the actuator 106 shown in FIG. 22.

[0075]FIG. 44 shows a detail around the head member of the ink jetrecording apparatus.

[0076]FIG. 45 shows other embodiment of the ink cartridge 180 shown inFIG. 44.

[0077]FIG. 46 shows further other embodiment of the ink cartridge 180.

[0078]FIG. 47 shows further other embodiment of the ink cartridge 180.

[0079]FIG. 48 shows further other embodiment of the ink cartridge 180.

[0080]FIG. 49 shows a plan cross sectional view of the further anotherembodiment of the ink cartridge according to the present invention.

[0081]FIG. 50 shows a plan cross sectional view of the further anotherembodiment of the ink cartridge according to the present invention.

[0082]FIG. 51 shows other embodiment of the ink cartridge using theactuator 106.

[0083]FIG. 52 is a cross sectional view of an embodiment of an inkcartridge as an embodiment of the liquid container according to thepresent invention.

[0084]FIG. 53 is a perspective view of the ink cartridge which storesplural types of inks, viewed from an outside thereof, according to anembodiment.

[0085]FIG. 54 is a cross sectional view showing an embodiment of a majorpart of the ink-jet recording apparatus suitable for the ink cartridgeshown in FIGS. 52 and 53.

[0086]FIG. 55 is a cross sectional view of an another embodiment of anink cartridge as an embodiment of the liquid container according to thepresent invention.

[0087]FIG. 56 shows further other embodiment of the ink cartridge usingthe actuator 106.

[0088]FIG. 57 shows further another embodiment of the ink cartridgeusing the actuator 106.

[0089]FIG. 58 shows further another embodiment of the ink cartridge 180.

[0090]FIG. 59 shows further another embodiment of the ink cartridge 180.

[0091]FIG. 60 shows further another embodiment of the ink cartridge 180.

[0092]FIG. 61 shows further another embodiment of the ink cartridge 180.

[0093]FIG. 62 shows further another embodiment of the ink cartridge 180.

[0094]FIG. 63 shows further another embodiment of the ink cartridge 180.

[0095]FIG. 64 shows further other embodiment of the ink cartridge 180.

[0096]FIG. 65 shows further other embodiment of the ink cartridge 180.

[0097]FIG. 66 shows further other embodiment of the ink cartridge 180.

[0098]FIG. 67 shows an embodiment around a recording head of part of theink cartridge and an ink jet recording apparatus which uses the actuator106.

[0099]FIG. 68 shows a detail around the head member of the ink jetrecording apparatus.

[0100]FIG. 69 is a cross sectional view of an embodiment of an inkcartridge as an embodiment of the liquid container according to thepresent invention.

[0101]FIG. 70 is a cross sectional view of an embodiment of an ink jetrecording apparatus and ink cartridge according to the presentinvention.

[0102]FIG. 71 is a cross sectional view of a further another embodimentof an ink cartridge as an embodiment of the liquid container accordingto the present invention.

[0103]FIG. 72 shows further another embodiment of the ink cartridgeusing the actuator 106.

[0104]FIG. 73 shows further another embodiment of the ink cartridgeusing the actuator 106.

[0105]FIG. 74 shows further another embodiment of the ink cartridgeusing the actuator 106.

[0106]FIG. 75 shows a cross section of an ink cartridge 180D which isfurther other embodiment of the ink cartridge 180 using actuator 106.

[0107]FIG. 76 shows further another embodiment of the ink cartridgeusing actuator 106.

[0108]FIG. 77 shows further another embodiment of the ink cartridgeusing actuator 106.

[0109]FIG. 78 shows further another embodiment of the ink cartridgeusing the actuator 106.

[0110]FIG. 79 shows further another embodiment of the ink cartridge 180.

[0111]FIG. 80 shows further another embodiment of the ink cartridge 180.

[0112]FIG. 81 shows further another embodiment of the ink cartridge 180.

[0113]FIG. 82 shows further another embodiment of the ink cartridge 180.

[0114]FIG. 83 shows further another embodiment of the ink cartridge 180.

[0115]FIG. 84 shows further another embodiment of the ink cartridge 180.

[0116]FIG. 85 shows further other embodiment of the ink cartridge usingthe actuator 106.

[0117]FIG. 86 shows further other embodiment of the ink cartridge 180.

[0118]FIG. 87 shows further other embodiment of the ink cartridge 180.

[0119]FIG. 88 shows an embodiment around a recording head of part of theink cartridge and an ink jet recording apparatus which uses the actuator106.

[0120]FIG. 87 shows further other embodiment of the ink cartridge 180.

[0121]FIG. 88 shows an embodiment around a recording head of part of theink cartridge and an ink jet recording apparatus which uses the actuator106.

[0122]FIG. 89 shows a detail around the head member of the ink jetrecording apparatus.

[0123]FIG. 90 is a cross sectional view of an embodiment of an inkcartridge for use with a single color, for example, the black ink.

[0124]FIG. 91 is a cross sectional view showing an embodiment of a majorpart of the ink-jet recording apparatus suitable for the ink cartridgeshown in FIG. 90.

[0125]FIG. 92 is a detailed cross sectional view of a subtank unit 33.

[0126]FIG. 93 is a cross sectional view showing an another embodiment ofthe ink cartridge.

[0127] FIGS. 94 shows manufacturing methods of the elastic wavegenerating device 3, 15, 16 and 17.

[0128] FIGS. 95 shows manufacturing methods of the elastic wavegenerating device 3, 15, 16 and 17.

[0129]FIG. 96 shows an ink cartridge according to another embodiment ofthe present invention.

[0130]FIG. 97 shows ink cartridges according to still anotherembodiments of the present invention.

[0131]FIG. 98 shows ink cartridges according to still anotherembodiments of the present invention.

[0132]FIG. 99 shows an ink cartridge according to still anotherembodiment of the present invention.

[0133]FIG. 100 shows a cross section of the ink-jet recording apparatusalone.

[0134]FIG. 101 is a cross section of the ink-jet recording apparatus towhich the ink cartridge 272 is mounted.

[0135]FIG. 102 shows an embodiment of the ink cartridge for use with asingle color, for instance, the black color.

[0136]FIG. 103 shows an ink cartridge 272 according to still anotherembodiment of the present invention.

[0137]FIG. 104 shows an ink cartridge 272 and an ink-jet recordingapparatus according to still another embodiment of the presentinvention.

[0138]FIG. 105 is a cross sectional view of an embodiment of an inkcartridge for use with a single color, for example, the black ink.

[0139]FIG. 106 is a cross sectional view of the bottom part of the inkcartridge of the present embodiment.

[0140]FIG. 107 is a cross sectional view showing an embodiment of amajor part of the ink-jet recording apparatus suitable for the inkcartridge shown in FIGS. 105 and 106.

[0141]FIG. 108 is a cross sectional view of another embodiment of asubtank unit 33.

[0142]FIG. 109 show ink cartridges according to still anotherembodiments of the present invention.

[0143]FIG. 110 shows an ink cartridge according to still anotherembodiment of the present invention.

[0144]FIG. 111 shows other embodiment of the through hole 1 c.

[0145]FIG. 112 is a slant view of the further other embodiment of theactuator.

[0146]FIG. 114 shows further other embodiment of the ink cartridge 180.

[0147]FIG. 114 shows further other embodiment of the ink cartridge 180.

[0148]FIG. 115 shows further other embodiment of the ink cartridge 180.

DETAILED DESCRIPTION OF THE INVENTION

[0149] The invention will now be described based on the preferredembodiments, which do not intend to limit the scope of the presentinvention, but exemplify the invention. All of the features and thecombinations thereof described in the embodiment are not necessarilyessential to the invention.

[0150] The basic concept of the present invention is to detect a stateof the liquid inside a liquid container by utilizing vibrationphenomena. The state of the liquid includes whether or not the liquid inthe liquid container is empty, amount of the liquid, level of theliquid, types of the liquid and combination of liquids. Several specificmethods realizing for detection of the state of the liquid inside theliquid container utilizing vibration phenomena are considered. Forexample, a method is considered in which the medium and the change ofits state inside the liquid container are detected in such a manner thatan elastic wave generating device generates an elastic wave inside theliquid container, and then the reflected wave which is thus reflected bythe liquid surface or a wall disposed counter thereto is captured. Thereis another method in which a change of acoustic impedance is detected byvibrating characteristics of a vibrating object.

[0151] As a method utilizing the change of the acoustic impedance, avibrating portion of a piezoelectric device or an actuator having apiezoelectric element therein is vibrated. Thereafter, a resonantfrequency or an amplitude of the back electromotive force waveform isdetected by measuring the back electromotive force which is caused byresidual vibration which remains in the vibrating portion, so as todetect the change of the acoustic impedance. As another method utilizingthe change of the acoustic impedance, the impedance characteristic oradmittance characteristic of the liquid is measured by a measuringapparatus such as an impedance analyzer and a transmission circuit, sothat the change of a current value or a voltage value, or the change ofthe current value or voltage value due to the frequency caused by thevibration given to the liquid is measured.

[0152] In the present embodiment, the medium in the liquid container andthe change of the status of the medium in the liquid container isdetected using the piezoelectric device or actuator to detect theresidual vibration remained in the vibrating section of thepiezoelectric device and the actuator.

[0153]FIG. 1 to FIG. 13 is a cross sectional view of an embodiment of anink cartridge for use with a single color, for example, the black ink asan embodiment of the liquid container according to the presentinvention. An ink cartridge according to the present embodimentcomprises a container 1 which contains liquid K, a ink supply port 2which supplies liquid K outside the container 1, an actuator 106 whichdetects ink consumption status inside the container 1, and a wavepreventing wall which provided at the position that faced to theactuator 106.

[0154] A packing ring 4 and a valve body 6 are provided in the inksupply port 2. Referring to FIG. 18, the packing ring 4 is engaged withthe ink supply needle 32 communicating with a recording head 31, in afluid-tight manner. The valve body 6 is constantly and elasticallycontacted against the packing ring 4 by way of a spring 5. When the inksupply needle 32 is inserted, the valve body 6 is pressed by the inksupply needle 32 so as to open an ink passage, so that ink inside thecontainer 1 is supplied to the recording head 31 via the ink supply port2 and the ink supply needle 32. On an upper wall of the container 1,there is mounted a semiconductor memory means 7 which stores data on inkinside the ink cartridge.

[0155]FIG. 1(A) shows a side cross sectional view of an embodiment ofthe ink cartridge according to the present invention. In FIG. 1 to FIG.4, the wave preventing wall 1192 a to 1192 d is extended horizontally tothe ink surface. Furthermore, the actuator 106 is mounted on the bottomface 1 a which is located lower side of the ink surface. As shown inFIG. 1(A), the ink supply port 2 that engages with the ink supply needleof the recording apparatus is provided on the container 1 which containsink. The actuator 106 is mounted on the outside the bottom face 1 a ofthe container 1 so that the actuator 106 can contacts with ink insidethe container 1 through the through hole 1 c which is provided on hecontainer 1. The actuator 106 is provided on the position which ishigher than the ink supply port 2 so that when ink K is almost used up,that is, at the time of the ink near end, the propagation of the elasticwave can change from ink to gas. The actuator 106 can be used as onlyfor the means of merely detecting the vibration generated in the inkcartridge without generating a vibration by itself.

[0156]FIG. 1(B) shows a cross sectional view from the front of anembodiment of the ink cartridge according to the present embodiment. Asshown in FIG. 1(B), the container 1 has a side wall 1020 which extendssubstantially vertical direction to the liquid surface. The wavepreventing wall 1192 a is fixed to the container 1 by mounting on theside wall 1020 of the container 1.

[0157] A gap is provided between the actuator 106 and the wavepreventing wall 1192 a. If ink is filled in the ink cartridge, ink isfilled in the gap between the actuator 106 and the wave preventing wall1192 a. On the other hand, the gap is designed such that ink is not heldin the gap between the actuator 106 and the wave preventing wall 1192 aif ink in the ink cartridge is used up. In other words, no capillaryforce for holding ink arises between the actuator 106 and the wavepreventing wall 1192 a.

[0158] Because the through hole 1 c is provided on the container 1, inkremains in the through hole 1 c even the ink inside the container 1 isconsumed. Therefore, even when the ink cartridge vibrates by such asscanning operation during the printing process and thus ink nearby theink supply port 2 rolls, ink does not mistakenly attach to the actuator106 because ink previously remains in the through hole 1 c. Thus, thereis only little possibility for the actuator 106 to mistakenly detect theexistence of ink.

[0159] The wave preventing wall is provided to face to the actuator 106in the ink cartridge according to the present embodiment. Therefore,even ink nearby the ink supply port 2 rolls, the wave preventing wallprevents the rolled ink to be contact with the actuator 106. Therefore,Thus, there is only little possibility for the actuator 106 tomistakenly detect the existence of ink.

[0160] Furthermore, bubbles may be generated by the waving of ink, whichis caused by the vibration of ink cartridge generated by such as thescanning operation during the printing process. Then, there is dangerthat the actuator 106 may detect mistakenly that there is no ink if thebubble attaches to the actuator 106 even if the ink is filled in thecontainer 1. However, according to the configuration of the presentembodiment, the wave preventing wall prevents the waving of ink aroundthe piezoelectric device even when the ink cartridge vibrates by such asthe scanning operation during the printing process. By preventing thewaving of ink around the piezoelectric device, the wave preventing wallprevents the generation of the bubbles. Furthermore, even the bubblesgenerate, the wave preventing wall prevents the bubbles to move close tothe actuator 106 and contact with the actuator 106 because the wavepreventing wall is provided such that the wave preventing wall faces tothe actuator 106.

[0161] There is no limitation of the size, shape, flexibility, andmaterial for the wave preventing wall. Therefore, the size of the wavepreventing wall can be made further larger or can be made furthersmaller. The thickness of the wave preventing wall can be made furtherthicker or can be made further thinner. Furthermore, the shape of thewave preventing wall can be square, rectangular, polygon, or an ellipse.Furthermore, the wave preventing wall can be made from the hard materialor flexible material. Furthermore, the wave preventing wall can be madefrom the air-tight or liquid-tight material. Conversely, the wavepreventing wall can be made from the breathability material or materialwhich can pas through liquid. As an example of the air-tight orliquid-tight material, there are plastic, tefron, nylon, polypropylene,or PET. On the other hand, as an example of the breath ability materialor a material which pass through liquid, there are porous materialconstituted by such as nylon or a material having a mesh structure.Furthermore, the porous material used for the wave preventing wall canbe negative pressure generating member.

[0162] Preferably, the container 1 and the wave preventing wall isformed by a same material such that both of the container 1 and the wavepreventing wall can be formed as one body. Then, the manufacturingprocess of the ink cartridge can be reduced.

[0163] Because ink cannot be supplied from the ink supply port 2 to therecording head if the pressure inside the ink cartridge becomesextremely negative with the ink consumption, airhole, not shown infigure, is provided on a part of the container so that the pressureinside the ink cartridge does not become extreme negative.

[0164]FIG. 2 shows a side cross sectional view of the other embodimentof the ink cartridge according to the present invention. As shown inFIG. 2, a wave preventing wall 1192 b is mounted on the side wall 1030which extends to the vertical direction to the ink surface. The crosssection viewed from the front of the ink cartridge according to thepresent embodiment is same as the cross section shown in one of FIG.1(B) or FIG. 3(B).

[0165] The wave preventing wall 1192 b of the ink cartridge of thepresent embodiment extends longer than the wave preventing wall 1192 aof the embodiment shown in FIG. 1. Therefore, the wave preventing wall1192 b can effectively protects the actuator 106 from the wave of ink.

[0166]FIG. 3(A) shows a side cross sectional view of the further otherembodiment of the ink cartridge according to the present invention. Asshown in FIG. 3(A), a side wall 1010 and a side wall 1030, which extendto the vertical direction to the ink surface, faces each other. The wavepreventing wall 1192 c extends from the side wall 1010 to the side wall1030.

[0167]FIG. 3(B) shows a cross sectional view from the front of the inkcartridge of FIG. 3(A). A gap is provided between the side wall 1020 andthe wave preventing wall 1192 c so that ink can pass through the gap.

[0168]FIG. 4 shows a side cross section of the further other embodimentof the ink cartridge according to the present invention. In the presentembodiment, the actuator 106 is provided on the sloped face formed onthe bottom face 1 a. The wave preventing wall 1192 d extends from theperiphery of the ink supply port 2 within the inside wall of thecontainer to face to the actuator 106.

[0169]FIG. 5(A) shows a side cross section of the further otherembodiment of the ink cartridge according to the present invention.

[0170] In FIG. 5 to FIG. 7, the actuator 106 is mounted on the side wall1030 which extends to the vertical direction to the ink surface.Furthermore, the wave preventing wall 1192 e to 1192 g extendssubstantially vertical to the ink surface, that is, parallel with theside wall 1030.

[0171] The wave preventing wall 1192 e is provided on the position wheredirectly faces to the actuator 106. The wave preventing wall 1192 eextends from the bottom face 1 a. Furthermore, a gap is provided betweenthe top wall 1040 and the top of wave preventing wall 1192 e.

[0172]FIG. 5(B) shows a cross sectional view from the front of the inkcartridge of FIG. 5(A). A gap is provided between the side wall 1020 andthe wave preventing wall 1192 e so that ink can pass through the gap.Because of the gap, ink does not remain in the actuator 106 side of thecontainer 1, which is formed by partitioning the container 1 by the wavepreventing wall 1192 e, even if ink is consumed. Therefore, the level ofink surface around the actuator 106 is always equal to the level of theink surface of the other region of the container 1. Thus, the actuator106 does not detect mistakenly the ink consumption status.

[0173] Furthermore, the length of the wave preventing wall 1192 e fromthe bottom face 1 a can be changed according to the height of theactuator 106 to the level of the ink surface and the probability of thegeneration of ink wave which is influenced by the viscosity of ink.Furthermore, interval of the gap between the wave preventing wall 1192eand the side wall 1020 can be changed according to the position of theactuator 106 on the width direction of the ink cartridge, the magnitudeof the vibrating region of the actuator 106, or the characteristic ofink.

[0174]FIG. 6(A) shows a side cross section of the further otherembodiment of the ink cartridge according to the present invention. theactuator 106 is mounted on the side wall 1030. A wave preventing wall1192 f is mounted on the position where directly faces to the actuator106. The wave preventing wall 1192 f extends from the top wall 1040.Furthermore, a gap is provided between the bottom face 1 a and the wavepreventing wall 1192 f.

[0175]FIG. 6(B) shows a cross sectional view from the front of the inkcartridge of FIG. 6(A). The wave preventing wall 1192 f is coupled tothe side wall 1020 liquid tightly so that ink can not pass throughbetween the wave preventing wall 1192 f and the side wall 1020. By thisconfiguration, ink remains only in the side of the actuator 106 which isformed by partitioning the container 1 by the wave preventing wall 1192f, even if ink is consumed. However, when ink surface reaches to thelower end of the wave preventing wall 1192 f, gas enters to the actuator106 side of the container 1 partitioned by the wave preventing wall 1192f. By the entering of the gas, ink remained in the actuator 106 side ofthe container 1 partitioned by the wave preventing wall 1192 f flows outto the ink supply port 2 side, then the medium exits around the actuator106 changes from ink to gas. Thereby the actuator 106 can detect thatthe ink inside the ink cartridge is in status of ink end. According tothe present embodiment, lower end 192 a determines the level of inksurface to be an ink end. Therefore, as far as the actuator 106 isprovided on the position upper than the lower end 192 a to the inksurface, actuator 106 can be located in any position on the wall face1030. An airhole, which introduces gas, is provided on the top wall ofthe ink supply port 2 side of the container 1 partitioned by the wavepreventing wall 1192 f.

[0176]FIG. 7(A) shows a side cross section of the further otherembodiment of the ink cartridge according to the present invention. Theactuator 106 is mounted on the side wall 1030 which is vertical to theink surface among the wall of the container 1. A wave preventing wall1192 g is provided on the position where directly faces to the actuator106. The wave preventing wall 1192 g extends from the bottom face 1 a tothe top wall 1040.

[0177]FIG. 7(B) shows a cross sectional view from the front of the inkcartridge of FIG. 7(A). A gap is provided between the wave preventingwall 1192 g and the side wall 1020 so that ink can pass through the gap.By this configuration, ink does not remain in the side of the actuator106 which is formed by partitioning the container 1 by the wavepreventing wall 1192 g, even if ink is consumed. Therefore, the level ofink surface around the actuator 106 is always equal to the level of inksurface of the other region of container 1. Furthermore, the interval ofthe gap between the wave preventing wall 1192 g and the side wall 1020can be changed according to the position of the actuator 106 on thewidth direction of the ink cartridge, or the characteristic of ink.

[0178]FIG. 8 to FIG. 11 show a side cross section of the further otherembodiment of the ink cartridge according to the present invention. Theactuator 106 is mounted on the side wall 1010 where the ink supply port2 is provided.

[0179] In FIG. 8, the wave preventing wall 1192 i is provided on theposition where directly faces to the actuator 106. The wave preventingwall 1192 i extends from the supply port wall 2 a which is a outsidewall of the ink supply port 2 among the inside wall nearby the inksupply port 2 of the ink cartridge. On the other hand, a gap is providedbetween the top wall 1040 and the wave preventing wall 1192 i.

[0180] Because the cross section viewed from the front of the inkcartridge of the present invention is similar to FIG. 5(B), the figureof which will be omitted for FIG. 8. There is a gap between the wavepreventing wall 1192 i and the side wall 1020. Because of the gap, inkdoes not remain in the actuator 106 side of the container 1, which isformed by partitioning the container 1 by the wave preventing wall, evenif ink is consumed 1192 i as the embodiment shown in FIG. 5. Therefore,the level of ink surface around the actuator 106 is always equal to thelevel of the ink surface of the other region of the container 1.

[0181] In FIG. 9, the wave preventing wall 1192 j is provided on theposition where directly faces to the actuator 106. The wave preventingwall 1192 j extends from the top wall 1040. On the other hand, a gap isprovided between the supply port wall 2 a and the wave preventing wall1192 j.

[0182] Because the cross section viewed from the front of the inkcartridge of the present invention is similar to FIG. 6(B), the figureof which will be omitted for FIG. 9. The wave preventing wall 1192 j iscoupled to the side wall 1020 liquid so that ink can not pass throughbetween the wave preventing wall 1192 j and the side wall 1020.Therefore, as the embodiment shown in FIG. 6, as far as the actuator 106is provided on the position upper than the lower end 192 a to the inksurface, the actuator 106 can be located in any position on the wallface 1030.

[0183] In FIG. 10, the wave preventing wall 1192 k is provided on theposition where directly faces to the actuator 106. The wave preventingwall 1192 k extends from the top wall 1040 to the supply port wall 2 a.

[0184] Because the cross section viewed from the front of the inkcartridge of the present invention is similar to FIG. 7(B), the figureof which will be omitted for FIG. 10. A gap is provided between the wavepreventing wall 1192 k and the side wall 1020 as shown in FIG. 7(B).Therefore, ink does not remain in the side of the actuator 106 which isformed by partitioning the container 1 by the wave preventing wall 1192k, even if ink is consumed as same as the embodiment of FIG. 5.Therefore, the level of ink surface around the actuator 106 is alwaysequal to the level of ink surface of the other region of container 1.

[0185]FIG. 11 to FIG. 13 show a side cross section of the further otherembodiment of the ink cartridge according to the present invention. Theactuator 106 is mounted on the boundary between the bottom face 1 a,which is located below the ink surface, and the side wall 1030, whichextends vertical to the ink surface.

[0186] In FIG. 11, a wave preventing wall 1192 m is fixed to thecontainer 1 such that one end of a wave preventing wall 1192 m isconnected to the bottom face 1 a, and the other end of which isconnected to the side wall 1030. The wave preventing wall 1192 m isprovided on the container 1 such that the wave preventing wall 1192 mdirectly faces to the actuator 106 and slopes to the ink surface. Thereis a gap between the side wall 1020 and the wave preventing wall 1192 mamong the wall of the container 1 in the present embodiment. Therefore,the level of ink surface around the actuator 106 is always equal to thelevel of ink surface of the other region of container 1 even if ink isconsumed. Furthermore, the shape of the wave preventing wall 1192 m ofthe present embodiment is substantially plane shape.

[0187] Because the ink cartridge according the present embodimentmounting the actuator 106 on the boundary of the wall of the container1, the positioning of the actuator 106 on the container 1 during themanufacturing of the ink cartridge becomes easy. Moreover, because thelength or the width of the wave preventing wall 1192 m can be shorten,the quantity of the material used for manufacturing the wave preventingwall 1192 m is reduced. Furthermore, even in the case of manufacturingthe wave preventing wall 1192 m as a independent material with thecontainer 1, it is relatively easy to positioning the wave preventingwall 1192 m on the boundary of the wall of the container 1. Therefore,the manufacturing of the ink cartridge 180 becomes easy.

[0188] In FIG. 12, the position of mounting the actuator 106 and thewave preventing wall 1192 n on the container 1 is same as the embodimentof the FIG. 11. On the other hand, the shape of the wave preventing wall1192 n is a part of the spherical shell in the present embodiment. Byshaping the wave preventing wall 1192 n in a shape of spherical shell,the distance between the actuator 106 and the all the part of the wavepreventing wall 1192 n becomes equal. Thereby the wave preventing wall1192 n does not influence the residual vibration detected by theactuator 106.

[0189] Furthermore, the wave preventing wall 1192 n can be formed as apart of the hollow cylindrical shape.

[0190] In FIG. 13, the position of mounting the actuator 106 and thewave preventing wall 1192 p on the container 1 is same as the embodimentof the FIG. 11. On the other hand, the wave preventing wall 1192 p isformed in an L-shape in the present embodiment. The wave preventing wall1192 p is provided on the container 1 such that the wave preventing wall1192 p has a same distance with the side wall 1030 and the bottom face 1a. By shaping the wave preventing wall 1192 n in a L-shape and reducingthe gap between the wave preventing wall 1192 p and the actuator 106 aslong as the capillary force does not arise between the wave preventingwall 1192 p and the actuator 106, the waving and bubbling of ink aroundthe actuator 106 can be effectively prevented.

[0191]FIG. 14 is a perspective view of the ink cartridge which storesplural types of inks, viewed from a back side thereof, according to anembodiment. A container 8 is divided by division walls into three inkchambers 9, 10 and 11. Ink supply ports 12, 13 and 14 are formed for therespective ink chambers. In a bottom face 8 a of the respective inkchambers 9, 10 and 11, the respective actuator 15, 16 and 17 are mountedon the container 8 so that the actuator can contact with the ink whichis housed in each ink chamber via the through hole provided on thecontainer 8.

[0192] Each of three different wave preventing walls, not shown in thefigure, is provided on the position of each of inside of the inkcontainer 9, 10 and 11 such that the each of the wave preventing wallsfaces to the each of actuators 15, 16, and 17.

[0193]FIG. 15 is a perspective view of the ink cartridge which storesplural types of inks, viewed from a back side thereof, according to anembodiment. A container 8 is divided by partition walls into three inkchambers 9, 10 and 11. Ink supply ports 12, 13 and 14 are formed for therespective ink chambers. In a side wall 1028 which extends vertically tothe ink surface of the respective ink chambers 9, 10 and 11, therespective actuators 15, 16 and 17 are mounted on the container 8. Eachof the actuators 15, 16, and 17 is mounted on the each of the inkchambers 9, 10, 11 so that the each of the actuators 15, 16, and 17 cancontact with the ink which is housed in each ink chamber via the throughhole, not shown in the figure, provided on the container 8. The actuator16 is mounted at one of the partition wall, which is provided betweenthe ink chamber 9 and the ink chamber 10, and the partition wall, whichis provided between the ink chamber 10 and the ink chamber 11.

[0194] Each of the wave preventing walls, not shown in the figure, isprovided inside the each of the ink chamber 9, 10, and 11 such that eachof the wave preventing walls faces to the actuators 15, 16, and 17 andextends to the vertical direction to the ink surface.

[0195]FIG. 16 is a perspective view of the ink cartridge which storesplural types of inks, viewed from a back side thereof, according to anembodiment. A container 8 is divided by partition walls into three inkchambers 9, 10 and 11. Ink supply ports 12, 13 and 14 are formed for therespective ink chambers. Each of actuators 15, 16 and 17 is mounted onthe container 8 just nearby the each of the ink supply port 12, 13, and14, respectively. Each of the actuators 15, 16, and 17 is mounted on theeach of the ink chambers 9, 10, 11 so that the each of the actuators 15,16, and 17 can contact with the ink which is housed in each ink chambervia the through hole, not shown in the figure, provided on the container8.

[0196] Each of the wave preventing walls, not shown in the figure, isprovided inside the each of the ink chamber 9, 10, and 11 such that eachof the wave preventing walls faces to the actuators 15, 16, and 17 asshown in FIG. 8 to FIG. 11.

[0197]FIG. 17 is a perspective view of the ink cartridge which storesplural types of inks, viewed from a back side thereof, according to anembodiment. A container 8 has same constitute element as shown in FIG.14 to FIG. 16. A sloped face which slopes to the ink surface is providedon the bottom face 8 a. Each of actuators 15, 16 and 17 is mounted onthe sloped face 1025 of each of the ink chambers 9, 10, and 11.

[0198] Each of the wave preventing walls, not shown in the figure, isprovided inside the each of the ink chamber 9, 10, and 11 as shown inFIG. 4.

[0199] Furthermore, the actuators 15, 16, and 17 can be provided on theboundary of the walls that adjoin each other in the container 8. In thiscase, each of the wave preventing walls is provided inside the each ofthe ink chambers 9, 10, and 11 as shown in FIG. 11 to FIG. 13.

[0200]FIG. 18 is a cross sectional view showing an embodiment of a majorpart of the ink-jet recording apparatus suitable for the ink cartridgeshown in FIG. 1. A carriage 30 capable of reciprocating in the directionof the width of the recording paper is equipped with a subtank unit 33,while the recording head 31 is provided in a lower face of the subtankunit 33. Moreover, the ink supply needle 32 is provided in an inkcartridge mounting face side of the subtank unit 33. In the presentembodiment, the ink cartridge shown in FIG. 1 is used. Therefore, thewave preventing wall 1192 a is mounted on the position which faces tothe actuator 106. However, the ink cartridge shown in FIG. 2 to FIG. 17can be used instead of the ink cartridge shown in FIG. 1. Therefore, thewave preventing wall shown in FIG. 2 top FIG. 17 can be used for thepresent embodiment.

[0201]FIG. 19 is a detailed cross sectional view of a subtank unit 33 asan embodiment of the liquid container according to the presentinvention. The subtank unit 33 comprises the ink supply needle 32, theink chamber 34, a flexible valve 36 and a filter 37. In the ink chamber34, the ink is housed which is supplied from the ink cartridge via inksupply needle 32. The flexible valve 36 is so designed that the flexiblevalve 36 is opened and closed by means of the pressure differencebetween the ink chamber 34 and the ink supply passage 35. The subtankunit 33 is so constructed that the ink supply passage 35 is communicatedwith the recording head 31 so that the ink can be supplied up to therecording head 31.

[0202] Furthermore, the actuator 106 can be mounted on the side wall1050 which extends to vertical direction to the ink surface among thewall of the subtank unit 33. The actuator 106 is mounted on the sidewall 1050 so that the actuator 106 can contacts with ink inside the inkchamber 34 through the through hole 1001 c which is provided on the sidewall 1050. The wave preventing wall 1192 q extends from the filter 37 tothe upward direction to the ink surface so that the wave preventing wall1192 q faces to the actuator 106. A gap is provided between the top wall1060, which locates upward the ink surface, and the wave preventing wall1192 q.

[0203] A gap is provided between the actuator 106 and the wavepreventing wall 1192 q. If ink is filled in the ink cartridge, ink isfilled in the gap between the actuator 106 and the wave preventing wall1192 q. On the other hand, if the ink inside the ink cartridge isconsumed, ink is not held in the gap between the actuator 106 and thewave preventing wall 1192 q. That is, the capillary force, which holdsink, does not works between the actuator 106 and the wave preventingwall 1192 q.

[0204] The cross section of the subtank unit 33 viewed from thedirection of the side wall 1050 is similar to the cross section of theink cartridge shown in FIG. 5(B). A gap is provided between the sidewall, not shown in the figure, which adjacent to the side wall 1050 andthe wave preventing wall 1192 q. The level of the ink surface around theactuator 106 is always equal to the level of the ink surface of theother region of the container 1. Therefore, with the consumption of theink inside the ink chamber 34, the level of ink surface between the sidewall 1050 and the wave preventing wall 1192 q also decreases. Theactuator 106 thereby does not mistakenly detect the ink consumptionstatus.

[0205] Furthermore, the length of the wave preventing wall 1192 q fromthe filter 37 can be changed according to the position of the actuator106 to the level of the ink surface and the probability of thegeneration of ink wave which is influenced by the viscosity of ink.Furthermore, interval of the gap between the wave preventing wall 1192 qand the side wall 1020 can be changed according to the position of theactuator 106 on the subtank unit 33, the magnitude of the vibratingregion of the actuator 106, or the characteristic of ink.

[0206] Referring to FIG. 18, when the ink supply port 2 of the container1 is inserted through the ink supply needle 32 of the subtank unit 33,the valve body 6 recedes against the spring 5, so that an ink passage isformed and the ink inside the container 1 flows into the ink chamber 34.At a stage where the ink chamber 34 is filled with ink, a negativepressure is applied to a nozzle opening of the recording head 31 so asto fill the recording head with ink. Thereafter, the recording operationis performed.

[0207] When the ink is consumed in the recording head 31 by therecording operation, a pressure in the downstream of the flexible valve36 decreases. Then, the flexible valve 36 is positioned away from avalve body 38 so as to become opened as shown in FIG. 19. When theflexible valve 36 is opened, the ink in the ink chamber 34 flows intothe recording head 31 through the ink passage 35. Accompanied by the inkwhich has flowed into the recording head 31, the ink in the container 1flows into the subtank unit 33 via the ink supply needle 32.

[0208] Moreover, the actuator 106 and the wave preventing wall areprovided at least one of the ink cartridge and the subtank unit.However, the actuator 106 and the wave preventing wall can be providedboth of the ink cartridge and the subtank unit.

[0209] By providing the actuator 106 and the wave preventing wall onboth of the ink cartridge and the subtank unit, the ink end status ofthe ink cartridge and the subtank unit can be accurately detected. Forexample, the recording apparatus can be set to stop the recordingoperation when one of the cases arises such that the number of thedroplets discharged from the recording head reach to the predeterminednumber of droplets during the measuring of the number of droplets afterthe actuator 106, which is mounted on the ink cartridge, detects the inkend or that the actuator 106 mounted on the subtank unit 33 detects theink end.

[0210] Furthermore, the recording apparatus can be set to stop therecording operation when both of the cases arises such that the numberof the droplets discharged from the recording head reach to thepredetermined number of droplets after the actuator 106, which ismounted on the ink cartridge, detects the ink end and that the actuator106 mounted on the subtank unit 33 detects the ink end.

[0211] While the recording apparatus is operating, a drive signal issupplied to the actuator 106 at a period which is set in advance.

[0212]FIG. 20 is a cross sectional view of another embodiment of asubtank unit 33 of the liquid container according to the presentinvention. The actuator 106 is mounted on the side wall 1050. The wavepreventing wall 1192 r extends from the top wall 1060, which is locatedupside of the ink surface, downward to the ink surface. There is a gapbetween the lower end 192 a of the wave preventing wall 1192 r and thefilter 37. Moreover, a gap is provided between the wave preventing wall1192 r and the side wall adjacent to the side wall 1050. No capillaryforce, which holds ink, arises between the wave preventing wall 1192 rand the actuator 106 as similar to the embodiment shown in FIG. 19.

[0213] Because a gap is provided between the wave preventing wall 1192 rand the side wall adjacent to the side wall 1050, the level of the inksurface around the actuator 106 is always equal to the level of the inksurface of the other region of the container 34. Therefore, the actuator106 detects the ink end status by detecting the ink surface at themounting position of the actuator 106.

[0214]FIG. 21 is a cross sectional view of further another embodiment ofa subtank unit 33 of the liquid container according to the presentinvention. The actuator 106 is mounted on the side wall 1050. The wavepreventing wall 1192 s extends from the top wall 1060 until the filter37. No capillary force, which holds ink, arises between the wavepreventing wall 1192 s and the actuator 106 as similar to the embodimentshown in FIG. 19.

[0215] Furthermore, a gap is provided between the wave preventing wall1192 s and the side wall adjacent to the side wall 1050. Therefore, thelevel of the ink surface around the actuator 106 is always equal to thelevel of the ink surface of the other region of the container 34.

[0216]FIGS. 22 and 23 shows a detail and equivalent circuit of anactuator 106, which is an embodiment of the piezoelectric device of thepresent invention. The actuator explained herein is used at least forthe method which detects the liquid consumption status in the liquidcontainer by detecting a change in acoustic impedance. Especially, theactuator is used for the method which detects the liquid consumptionstatus in the liquid container by detecting at least the change inacoustic impedance by detecting the resonant frequency from residualvibration. FIG. 22(A) is an enlarged plan view of the actuator 106. FIG.22(B) shows a B-B cross-section of the actuator 106. FIG. 22(C) shows aC-C cross-section of the actuator 106. FIGS. 23(A) and 23(B) shows anequivalent circuit of the actuator 106. Each of FIGS. 23(C) and 23(D)shows the actuator 106 and around the actuator 106, and the equivalentcircuit of the actuator 106 when an ink is filled in the ink cartridge.FIGS. 23(E) and 23(F) shows the actuator 106 and around the actuator106, and the equivalent circuit of the actuator 106 when there is no inkin the ink cartridge.

[0217] The actuator 106 includes abase plate 178, a vibrating plate 176,a piezoelectric layer 160, an upper electrode 164 and a lower electrode166, an upper electrode terminal 168, a lower electrode terminal 170,and a supplementary electrode 172. The base plate 178 has a circularshape opening 161 on approximately its center. The vibrating plate 176is provided on one of the face, which is called as “right side” infollowing, of the base plate 178 such as to cover the opening 161. Thepiezoelectric layer 160 is disposed on right side of the surface of thevibrating plate 176. The upper electrode 164 and the lower electrode 166sandwich the piezoelectric layer 160 from both sides. The upperelectrode terminal 168 connects to the upper electrode 164 electrically.The lower electrode terminal 170 connects to the lower electrode 166electrically. The supplementary electrode 172 is disposed between theupper electrode 164 and the upper electrode terminal 168 and connectsboth of the upper electrode 164 and the upper electrode terminal 168.Each of the piezoelectric layer 160, upper electrode 164, and the lowerelectrode 166 has a circular portion as its main portion. Each of thecircular portion of the piezoelectric layer 160, the upper electrode164, and the lower electrode 166 form a piezoelectric element.

[0218] The vibrating plate 176 is formed on the right side of thesurface of the base plate 178 to cover the opening 161. The cavity 162is formed by the portion of the vibrating plate 176, which faces theopening 161, and the opening 161 of the on the surface of the base plate178 The face of the base plate 178 which is opposite side of thepiezoelectric element, called as “back side” in following, is faced withthe liquid container side. The cavity 162 is constructed such that thecavity 162 contacts with liquid. The vibrating plate 176 is mounted onthe base plate 178 such that the liquid does not leak to the right sideof the surface of the base plate 178 even if the liquid enters insidethe cavity 162.

[0219] The lower electrode 166 is located on the right side of thevibrating plate 176, that is, opposite side against the liquidcontainer. The lower electrode 166 is provided on the vibrating plate176 such that the center of the circular portion of the lower electrode166, which is a main portion of the lower electrode 166, and the centerof the opening 161 substantially matches. The area of the circularportion of the lower electrode 166 is set to be smaller than the area ofthe opening 161. The piezoelectric layer 160 is formed on the right sideof the surface of the lower electrode 166 such that the center of thecircular portion and the center of the opening 161 substantially match.The area of the circular portion of the piezoelectric layer 160 is setto be smaller than the area of the opening 161 and larger than the areaof the circular portion of the lower electrode 166.

[0220] The upper electrode 164 is formed on the right side of thesurface of the piezoelectric layer 160 such that the center of thecircular portion, which is a piezoelectric layer 160, and the center ofthe opening 161 substantially match. The area of the circular portion ofthe upper electrode 164 is set to be smaller than the area of thecircular portion of the opening 161 and the piezoelectric layer 160 andlarger than the area of the circular portion of the lower electrode 166.

[0221] Therefore, the main portion of the piezoelectric layer 160 has astructure to be sandwiched by the main portion of the upper electrode164 and the main portion of the lower electrode each from right sideface and back side face, and thus the main portion of the piezoelectriclayer 160 can effectively drive and deform the piezoelectric layer 160.The circular portion, which is a main portion of each of thepiezoelectric layer 160, the upper electrode 164, and the lowerelectrode 166, forms the piezoelectric element in the actuator 106. Asexplained above, the electric element contacts with the vibrating plate.Within the circular portion of the upper electrode 164, circular portionof the piezoelectric layer 160, the circular portion of the lowerelectrode, and the opening 161, the opening 161 has the largest area. Bythis structure, the vibrating region which actually vibrates within thevibrating plate is determined by the opening 161. Furthermore, each ofthe circular portion of the upper electrode 164 and the circular portionof the piezoelectric layer 160 and the circular portion of the lowerelectrode has smaller area than the area of the opening 161, Thevibrating plate becomes easily vibrate. Within the circular portion ofthe lower electrode 166 and the circular portion of the upper electrode164 which connects to the piezoelectric layer 160 electrically, thecircular portion of the lower electrode 166 is smaller than the circularportion of the upper electrode 164. Therefore, the circular portion ofthe lower electrode 166 determines the portion which generates thepiezoelectric effect within the piezoelectric layer 160.

[0222] The center of the circular portion of the piezoelectric layer160, the upper electrode 164, and the lower electrode 166, which formthe piezoelectric element, substantially match to the center of theopening 161. Moreover, the center of the circular shape opening 161,which determines the vibrating section of the vibrating plate 176, isprovided on the approximately center of the actuator 106. Therefore, thecenter of the vibrating section of the actuator 106 matches to thecenter of the actuator 106. Because the main portion of thepiezoelectric element and the vibrating section of the vibrating plate176 have a circular shape, the vibrating section of the actuator 106 issymmetrical about a center of the actuator 106.

[0223] Because the vibrating section is symmetrical about a center ofthe actuator 106, the excitation of the unnecessary vibration occurredowing to the asymmetric structure can be prevented. Therefore, theaccuracy of detecting the resonant frequency increases. Furthermore,because the vibrating section is symmetric about the center of theactuator 106, the actuator 106 is easy to manufacture, and thus theunevenness of the shape for each of the piezoelectric element can bedecreased. Therefore, the unevenness of the resonant frequency for eachof the piezoelectric element 174 decreases. Furthermore, because thevibrating section has an isotropic shape, the vibrating section isdifficult to be influenced by the unevenness of the fixing during thebonding process. That is, the vibrating section is bonded to the liquidcontainer uniformly. Therefore, the actuator 106 is easy to assemble tothe liquid container.

[0224] Furthermore, because the vibrating section of the vibrating plate176 has a circular shape, the lower resonant mode, for example, theprimary resonant mode dominates on the resonant mode of the residualvibration of the piezoelectric layer 160, and thus the single peakappears on the resonant mode. Therefore, the peak and the noise can bedistinguished clearly so that the resonant frequency can be clearlydetected. Furthermore, the accuracy of the detection of the resonantfrequency can be further increased by enlarge the area of the vibratingsection of the circular shape vibrating plate 176 because the differenceof the amplitude of the counter electromotive force and the differenceof the amplitude of the resonant frequency occurred by whether theliquid exists inside the liquid container increase.

[0225] The displacement generated by the vibration of the vibratingplate 176 is larger than the displacement generated by the vibration ofthe base plate 178. The actuator 106 has a two layers structure that isconstituted by the base plate 178 having a small compliance which meansit is difficult to be displaced by the vibration, and the vibratingplate 176 having a large compliance which means it is easy to bedisplaced by the vibration. By this two layers structure, the actuator106 can be reliably fixed to the liquid container by the base plate 178and at the same time the displacement of the vibrating plate 176 by thevibration can be increased. Therefore, the difference of the amplitudeof the counter electromotive force and the difference of the amplitudeof the resonant frequency depended on whether the liquid exists insidethe liquid container increases, and thus the accuracy of the detectionof the resonant frequency increases. Furthermore, because the complianceof the vibrating plate 176 is large, the attenuation of the vibrationdecreases so that the accuracy of the detection of the resonantfrequency increases. The node of the vibration of the actuator 106locates on the periphery of the cavity 162, that is, around the marginof the opening 161.

[0226] The upper electrode terminal 168 is formed on the right side ofthe surface of the vibrating plate 176 to be electrically connected tothe upper electrode 164 through the supplementary electrode 172. Thelower electrode terminal 170 is formed on the right side of the surfaceof the vibrating plate 176 to be electrically connected to the lowerelectrode 166. Because the upper electrode 164 is formed on the rightside of the piezoelectric layer 160, there is a difference in depth thatis equal to the sum of the thickness of the piezoelectric layer 160 andthe thickness of the lower electrode 166 between the upper electrode 164and the upper electrode terminal 168. It is difficult to fill thisdifference in depth only by the upper electrode 164, and even it ispossible to fill the difference in depth by the upper electrode 164, theconnection between the upper electrode 164 and the upper electrodeterminal 168 becomes weak so that the upper electrode 164 will be cutoff. Therefore, this embodiment uses the supplementary electrode 172 asa supporting member to connects the upper electrode 164 and the upperelectrode terminal 168. By this supplementary electrode 172, both of thepiezoelectric layer 160 and the upper electrode 164 are supported by thesupplementary electrode 172, and thus the upper electrode 164 can havedesired mechanical strength, and also the upper electrode 164 and theupper electrode terminal 168 can be firmly connected.

[0227] The piezoelectric element and the vibrating section which facesto the piezoelectric element within the vibrating plate 176 constitutethe vibrating section which actually vibrates in the actuator 106.Moreover, it is preferable to form the actuator 106 in one body byfiring together the member included in the actuator 106. By forming theactuator 106 as one body, the actuator 106 becomes easy to be handled.Further, the vibration characteristic increases by increasing thestrength of the base plate 178. That is, by increasing the strength ofthe base plate 178, only the vibrating section of the actuator 106vibrates, and the portion other than the vibrating section of theactuator 106 does not vibrates. Furthermore, the prevention of thevibration of the portion other than the vibrating section of theactuator 106 can be achieved by increasing the strength of the baseplate 178 and at the same time forming the actuator 106 as thinner andsmaller as possible and forming the vibrating plate 176 as thinner aspossible.

[0228] It is preferable to use lead zirconate titanate (PZT), leadlanthanum zirconate titanate (PLZT), or piezoelectric membrane withoutusing lead as a material for the piezoelectric layer 160. It ispreferable to use zirconia or alumina as a material of the base plate178. Furthermore, it is preferable to use same material as base plate178 for a material of vibrating plate 176. The metal such as gold,silver, copper, platina, aluminum, and nickel having a electricalconductivity can be used for the material of the upper electrode 164,the lower electrode 166, the upper electrode terminal 168, and the lowerelectrode terminal 170.

[0229] The actuator 106 constructed as explained above can be applied tothe container which contains liquid. For example, the actuator 106 canbe mounted on an ink cartridge used for the ink jet recording apparatus,an ink tank, or a container which contains washing liquid to wash therecording head.

[0230] The actuator 106 shown in the FIGS. 22 and 23 is mounted on thepredetermined position on the liquid container so that the cavity 162can contact w3ith the liquid contained inside the liquid container. Whenthe liquid container is filled with liquid sufficiently, the inside andoutside of the cavity 162 is filled with liquid. On the other hand, ifthe liquid inside liquid container consumed and the liquid leveldecreased under the mounting position of the actuator, there areconditions that liquid does not exit inside the cavity 162 or thatliquid is remained only in the cavity 162 and air exits on outside thecavity 162. The actuator 106 detects at least the difference in theacoustic impedance occurred by this change in condition. By thisdetection of the difference in acoustic impedance, the actuator 106 candetects the whether the liquid is sufficiently filled in the liquidcontainer or liquid is consumed more than predetermined level.Furthermore, the actuator 106 can detects the type of the liquid insidethe liquid container.

[0231] The principle of the detection of the liquid level by theactuator will be explained.

[0232] To detect the acoustic impedance of a medium, an impedancecharacteristic or an admittance characteristic is measured. To measurethe impedance characteristic or the admittance characteristic, forexample, transmission circuit can be used. The transmission circuitapplies a constant voltage on the medium and measure a current flowthrough the medium with changing a frequency. The transmission circuitprovides a constant current to the medium and measures a voltage appliedon the medium with changing a frequency. The change in current value andthe voltage value measured at the transmission circuit shows the changein acoustic impedance. Furthermore, the change in a frequency fm, whichis a frequency when the current value or the voltage value becomesmaximum or minimum, also shows the change in acoustic impedance.

[0233] Other than method shown above, the actuator can detects thechange in the acoustic impedance of the liquid using the change only inthe resonant frequency. The piezoelectric element, for example, can beused in a case of using the method of detecting the resonant frequencyby measuring the counter electromotive force generated by the residualvibration, which is remained in the vibrating section after thevibration of the vibrating section of the actuator, as a method of usingthe change in the acoustic impedance of the liquid. The piezoelectricelement is element which generates the counter electromotive force byresidual vibration remained in the vibrating section of the actuator.The magnitude of the counter electromotive force changes with theamplitude of the vibrating section of the actuator. Therefore, thelarger the amplitude of the vibrating section of the actuator, theeasier to detect the resonant frequency. Moreover, depends on thefrequency of the residual vibration at the vibrating section of theactuator, the period, on which the magnitude of the counterelectromotive force changes, changes. Therefore, the frequency of thevibrating section of the actuator corresponds to the frequency of thecounter electromotive force. Here, the resonant frequency means thefrequency when the vibrating section of the actuator and the medium,which contacts to the vibrating section, are in a resonant condition.

[0234] To obtain the resonant frequency fs, the waveform obtained bymeasuring the counter electromotive force when the vibrating section andthe medium are in resonant condition is Fourier transformed. Because thevibration of the actuator is not a displacement for only one direction,but the vibration involves the deformation such as deflection andextension, the vibration has various kinds of frequency including theresonant frequency fs. Therefore, the resonant frequency fs is judged byFourier transforming the waveform of the counter electromotive forcewhen the piezoelectric element and the medium are in the resonantcondition and then specifying the most dominating frequency components.

[0235] The frequency fm is a frequency when the admittance of the mediumis maximum or the impedance is minimum. The frequency fm is differentfrom the resonant frequency fs with little value because of thedielectric loss and the mechanical loss. However, the frequency fm isgenerally used as substitution for resonant frequency because it needstime for deriving the resonant frequency fs from the frequency fm whichis actually measured. By inputting output of the actuator 106 to thetransmission circuit, the actuator 106 can at least detect the acousticimpedance.

[0236] It is proved by the experiment that there is almost nodifferences with the resonant frequency obtained by the method, whichmeasures the frequency fm by measuring the impedance characteristic andadmittance characteristic of the medium, and the method, which measuresthe resonant frequency fs by measuring the counter electromotive forcegenerated by the residual vibration at the vibrating section of theactuator.

[0237] The vibrating region of the actuator 106 is a portion whichconstitutes the cavity 162 that is determined by the opening 161 withinthe vibrating plate 176. When liquid is sufficiently filled in theliquid container, liquid is filled in the cavity 162, and the vibratingregion contacts with liquid inside the liquid container. When liquiddoes not exists in the liquid container sufficiently, the vibratingregion contacts with the liquid which is remained in the cavity insidethe liquid container, or the vibrating region does not contacts with theliquid but contacts with the gas or vacuum.

[0238] The cavity 162 is provided on the actuator 106 of the presentinvention, and it can be designed that the liquid inside the liquidcontainer remains in the vibrating region of the actuator 106 by thecavity 162. The reason will be explained as follows.

[0239] Depends on the mounting position and mounting angle of theactuator 106 on the liquid container, there is a case in which theliquid attaches to the vibrating region of the actuator even the liquidlevel in the liquid container is lower than the mounting position of theactuator. When the actuator detects the existence of the liquid onlyfrom the existence of the liquid on the vibrating region, the liquidattached to the vibrating region of the actuator prevents the accuratedetection of the existence of the liquid. For example, If the liquidlevel is lower than the mounting position of the actuator, and the dropof the liquid attaches to the vibrating region by the waving of theliquid caused by the shaking of the liquid container caused by themovement of the carriage, the actuator 106 will misjudges that there isenough liquid in the liquid container. In this way, the malfunction canbe prevented by using the actuator having cavity.

[0240] Furthermore, as shown in FIG. 23(E), the case when the liquiddoes not exit in the liquid container and the liquid of the liquidcontainer remains in the cavity 162 of the actuator 106 is set as thethreshold value of the existence of the liquid. That is, if the liquiddoes not exist around the cavity 162, and the amount of the liquid inthe cavity is smaller than this threshold value, it is judged that thereis no ink in the liquid container. If the liquid exist around the cavity162, and the amount of the liquid is larger than this threshold value,it is judged that there is ink in the liquid container. For example,when the actuator 106 is mounted on the side wall of the liquidcontainer, it is judged that there is no ink in the liquid containerwhen the liquid level inside the liquid container is lower than themounting position of the actuator 106, and it is judged that there isink inside the liquid container when the liquid level inside the liquidcontainer is higher than the mounting position of the actuator 106. Bysetting the threshold value in this way, the actuator 106 can judge thatthere is no ink in the liquid container even if the ink in the cavity isdried and disappeared. Furthermore, the actuator 106 can judge thatthere is no ink in the liquid container even if the ink attaches to thecavity again by shaking of the carriage after the ink in the cavitydisappears because the amount of the ink attaches to the cavity againdoes not exceed the threshold value.

[0241] The operation and the principle of detecting the liquid conditionof the liquid container from the resonant frequency of the medium andthe vibrating section of the actuator 106 obtained by measuring thecounter electromotive force will be explained reference to FIGS. 22 and23. A voltage is applied on each of the upper electrode 164 and thelower electrode 166 through the upper electrode terminal 168 and thelower electrode terminal 170. The electric field is generated on theportion of the piezoelectric layer 160 where the piezoelectric layer 160is sandwiched by the upper electrode 164 and the lower electrode 166. Bythis electric field, the piezoelectric layer 160 deforms. By thedeformation of the piezoelectric layer 160, the vibrating region withinthe vibrating plate 176 deflects and vibrates. For some period after thedeformation of the piezoelectric layer 160, the vibration withdeflection remains in the vibrating section of the actuator 106.

[0242] The residual vibration is a free oscillation of the vibratingsection of the actuator 106 and the medium. Therefore, the resonantcondition between the vibrating section and the medium can be easilyobtained by applying the voltage of a pulse wave or a rectangular waveon the piezoelectric layer 160. Because the residual vibration vibratesthe vibrating section of the actuator 106, the residual vibration alsodeforms the piezoelectric layer 160. Therefore, the piezoelectric layer160 generates the counter electromotive force. This counterelectromotive force is detected through the upper electrode 164, thelower electrode 166, the upper electrode terminal 168, and the lowerelectrode terminal 170. Because the resonant frequency can be specifiedby this detected counter electromotive force, the liquid consumptionstatus in the liquid container can be detected.

[0243] Generally, the resonant frequency fs can be expressed asfollowing.

fs=1/(2*π*(M*Cact)^(1/2)  (1)

[0244] where M denotes the sum of an inertance of the vibrating sectionMact and an additional inertance M′; Cact denotes a compliance of thevibrating section.

[0245]FIG. 22(C) shows a cross section of the actuator 106 when the inkdoes not exist in the cavity in the present embodiment. FIGS. 23(A) and23(B) shows the equivalent circuit of the vibrating section of theactuator 106 and the cavity 162 when the ink does not exist in thecavity.

[0246] The Mact is obtained by dividing the product of the thickness ofthe vibrating section and the density of the vibrating section by thearea of the vibrating section. Furthermore, as shown in the FIG. 23(A),the Mact can be expressed as following in detail.

Mact=Mpzt+Melectrode1+Melectrode2+Mvib  (2)

[0247] Here, Mpzt is obtained by dividing the product of the thicknessof the piezoelectric layer 160 in the vibrating section and the densityof the piezoelectric layer 160 by the area of the piezoelectric layer160. Melectrode1 is obtained by dividing the product of the thickness ofthe upper electrode 164 in the vibrating section and the density of theupper electrode 164 by the area of the upper electrode 164. Melectrode2is obtained by dividing the product of the thickness of the lowerelectrode 166 in the vibrating section and the density of the lowerelectrode 166 by the area of the lower electrode 166. Mvib is obtainedby dividing the product of the thickness of the vibrating plate 176 inthe vibrating section and the density of the vibrating plate 176 by thearea of the vibrating region of the vibrating plate 176. However each ofthe size of the area of the vibrating region of the piezoelectric layer160, the upper electrode 164, the lower electrode 166, and vibratingplate 176 have a relationship as shown above, the difference among eachof the area of the vibrating region is prefer to be microscopic toenable the calculation of the Mact from the thickness, density, and areaas whole of the vibrating section. Moreover, it is preferable that theportion other than the circular portion which is a main portion of eachof the piezoelectric layer 160, the upper electrode 164, and the lowerelectrode 166 is microscopic so that it can be ignored compared to themain portion. Therefore, Mact is sum of the inertance of the each of thevibrating region of the upper electrode 164, the lower electrode 166,the piezoelectric layer 160, and the vibrating plate 176 in the actuator106. Moreover, the compliance Cact is a compliance of the portion formedby the each of the vibrating region of the upper electrode 164, thelower electrode 166, the piezoelectric layer 160, and the vibratingplate 176.

[0248] FIGS. 23(A), 23(B), 23(D), and 23(F) show the equivalent circuitof the vibrating section of the actuator 106 and the cavity 162. Inthese equivalent circuits, Cact shows a compliance of the vibratingsection of the actuator 106. Each of the Cpzt, Celectrode1, Celectrode2,and Cvib shows the compliance of the vibrating section of thepiezoelectric layer 160, the upper electrode 164, the lower electrode166, and the vibrating plate 176. Cact can be shown as followingequation.

1/Cact=(1/Cpzt)+(1/Celectrode1)+(1/Celectrode2)+(1/Cvib)  (3)

[0249] From the equation (2) and (3), FIG. 23(A) can be expressed asFIG. 23(B).

[0250] The compliance Cact shows the volume which can accept the mediumby the deformation generated by the application of the pressure on theunit area of the vibrating section. In other words, the compliance Cactshows the easiness to be deformed.

[0251]FIG. 23(C) shows the cross section of the actuator 106 when theliquid is sufficiently filled in the liquid container, and the peripheryof the vibrating region of the actuator 106 is filled with the liquid.The M′max shown in FIG. 23(C) shows the maximum value of the additionalinertance when the liquid is sufficiently filled in the liquidcontainer, and the periphery of the vibrating region of the actuator 106is filled with the liquid. The M′max can be expressed as

M′max=(π*ρ/(2*k ³))*(2*(2*k*a)³/(3*π))/(π*a ²)²  (4)

[0252] where a denotes the radius of the vibrating section; ρ denotesthe density of the medium; and k denotes the wave number. The equation(4) applies when the vibrating region of the actuator 106 is circularshape having the radius of “a”. The additional inertance M′ shows thequantity that the mass of the vibrating section is increased virtuallyby the effect of the medium which exists around the vibrating section.

[0253] As shown in equation (4), the M′ max can changes significantly bythe radius of the vibrating section “a” and the density of the medium ρ.

[0254] The wave number k can be expressed by following equation.

k=2*π*fact/c  (5)

[0255] where fact denotes the resonant frequency of the vibratingsection when the liquid does not contact with the vibrating section; andc denotes the speed of the sound propagate through the medium.

[0256]FIG. 23(D) shows an equivalent circuit of the vibrating section ofthe actuator 106 and the cavity 162 as in the case of FIG. 23(C) whenthe liquid is sufficiently filled in the liquid container, and theperiphery of the vibrating region of the actuator 106 is filled with theliquid.

[0257]FIG. 23(E) shows the cross section of the actuator 106 when theliquid in the liquid container is consumed, and there is no liquidaround the vibrating region of the actuator 106, and the liquid remainsin the cavity 162 of the actuator 106. The equation (4) shows themaximum inertance M′max determined by such as the ink density ρ when theliquid container is filled with the liquid. On the other hand, if theliquid in the liquid container is consumed and liquid existed around thevibrating section of the actuator 106 becomes gas or vacuum with theliquid remaining in the cavity 162, the M′ can be expressed as followingequation.

M′=ρ*t/S  (6)

[0258] where t denotes the thickness of the medium related to thevibration; S denotes the area of the vibrating region of the actuator106. If this vibrating region is circular shape having a radius of “a”,the S can be shown as S=π*a². Therefore, the additional inertance M′follows the equation (4) when the liquid is sufficiently filled in theliquid container, and the periphery of the vibrating region of theactuator 106 is filled with the liquid. The additional inertance M′follows the equation (6) when the liquid in the liquid container isconsumed, and there is no liquid exits around the vibrating region ofthe actuator 106, and the liquid is remained in the cavity 162.

[0259] Here, as shown in FIG. 23(E), let the additional inertance M′,when the liquid in the liquid container is consumed, and there is noliquid exits around the vibrating region of the actuator 106, and theliquid is remained in the cavity 162, as M′cav to distinguish with theadditional inertance M′max, which is the additional inertance when theperiphery of the vibrating region of the actuator 106 is filled with theliquid.

[0260]FIG. 23(F) shows an equivalent circuit of the vibrating section ofthe actuator 106 and the cavity 162 in the case of FIG. 23(E) when theliquid in the liquid container is consumed, and there is no liquidaround the vibrating region of the actuator 106, and the liquid remainsin the cavity 162 of the actuator 106.

[0261] Here, the parameters related to the status of the medium aredensity of the medium ρ and the thickness of the medium t in equation(6). When the liquid is sufficiently filled in the liquid container, theliquid contacts with the vibrating section of the actuator 106. When theliquid is insufficiently filled in the liquid container, the liquid isremained in the cavity, or the gas or vacuum contacts with the vibratingsection of the actuator 106. If let the additional inertance during theprocess of the shifting from the M′max of FIG. 23(C) to the M′var ofFIG. 23(E) when the liquid around the actuator 106 is consumed, becausethe thickness of the medium t changes according to the containing statusof the liquid in the liquid container, the additional inertance M′varchanges, and resonant frequency also changes. Therefore, the existenceof the liquid in the liquid container can be detected by specify theresonant frequency. Here, if let t=d, as shown in FIG. 23(E) and usingthe equation (6) to express the m′cav, the equation (7) can be obtainedby substituting the thickness of the cavity “d” into the “t” in theequation (6).

M′cav=ρ*d/S  (7)

[0262] Moreover, if the medium are different types of liquid with eachother, the additional inertance M′ changes and resonant frequency fsalso changes because the density ρ is different according to thedifference of the composition. Therefore, the types of the liquid can bedetected by specifying the resonant frequency fs. Moreover, when onlyone of the ink or air contacts with the vibrating section of theactuator 106, and the ink and air is not existing together, thedifference in M′ can be detected by calculating the equation (4).

[0263]FIG. 24(A) is a graph which shows the relationship between the inkquantity inside the ink tank and the resonant frequency fs of the inkand the vibrating section. Here, the case for the ink will be explainedas an example of the liquid. The vertical axis shows the resonantfrequency fs, and the horizontal axis shows the ink quantity. When theink composition is constant, the resonant frequency increases accordingto the decreasing of the ink quantity.

[0264] When ink is sufficiently filled in the ink container, and ink isfilled around the vibrating region of the actuator 106, the maximumadditional inertance M′max becomes the value shown in the equation (4).When the ink is consumed, and there is no ink around the vibratingregion of the actuator 106, and the ink remains in the cavity 162, theadditional inertance M′var is calculated by the equation (6) based onthe thickness of the medium t. Because the “t” used in the equation (6)is the thickness of the medium related to the vibration, the processduring which the ink is consumed gradually can be detected by formingthe “d” (refer to FIG. 22(B)) of the cavity 162 of the actuator 106 assmall as possible, that is, forming the thickness of the base plate 178as sufficiently thinner as possible (refer to FIG. 23(C)). Here, let thet-ink as the thickness of the ink involved with the vibration, andt-ink-max as the t-ink when the additional inertance is M′max. Forexample, the actuator 106 is mounted on the bottom of the ink cartridgehorizontally to the surface of the ink. If ink is consumed, and the inklevel becomes lower than the height t-ink-max from the actuator 106, theM′var gradually changes according to the equation (6), and the resonantfrequency fs gradually changes according to the equation (1). Therefore,until the ink level is within the range of “t”, the actuator 106 cangradually detect the ink consumption status.

[0265] Furthermore, by enlarge or lengthen the vibrating section of theactuator 106 and arrange the actuator 106 along a lengthwise direction,the “S” in the equation (6) changes according to the change of ink levelwith ink consumption. Therefore, the actuator 106 can detect the processwhile the ink is gradually consumed. For example, the actuator 106 ismounted on the side wall of the ink cartridge perpendicularly to the inksurface. When the ink is consumed and the ink level reaches to thevibrating region of the actuator 106, because the additional inertanceM′ decreases with the decreasing of the ink level, the resonantfrequency fs gradually increases according to the equation (1).Therefore, unless the ink level is within the range of the radius 2 a ofthe cavity 162 (refer to FIG. 23(C)), the actuator 106 can graduallydetect the ink consumption status.

[0266] The curve X in FIG. 24(A) shows the relationship between the inkquantity contained inside of the ink tank and the resonant frequency fsof the ink and the vibrating section when the vibrating region of theactuator 106 is formed sufficiently large or long. It can be understandthat the resonant frequency fs of the ink and vibrating sectiongradually changes with the decrease of the ink quantity inside the inktank.

[0267] In detail, the case when the actuator 106 can detect the processof the gradual consumption of the ink is the case when the liquid andgas having different density with each other are existed together andalso involved with vibration. According to the gradual consumption ofthe ink, the liquid decreases with increasing of the gas in the mediuminvolved with the vibration around the vibrating region of the actuator106. For example, the case when the actuator 106 is mounted on the inkcartridge horizontally to the ink surface, and t-ink is smaller than thet-ink-max, the medium involved with the vibration of the actuator 106includes both of the ink and the gas. Therefore, the following equation(8) can be obtained if let the area of the vibrating region of theactuator 106 as S and express the status when the additional inertanceis below M′max in the equation (4) by additional mass of the ink and thegas.

M′=M′air+M′ink=ρair * t-air/S+ρink * t-ink/S  (8)

[0268] where M′max is an inertance of an air; M′ink is an inertance ofan ink; ρair is a density of an air; ρink is a density of an ink; t-airis the thickness of the air involved with the vibration; and t-ink isthe thickness of the ink involved with the vibration. In case when theactuator 106 is mounted on the ink cartridge approximately horizontallyto the ink surface, the t-air increases and the t-ink decreases with theincrease of the gas and the decrease of the ink within the mediuminvolved with the vibration around the vibrating region of the actuator106. The additional inertance M′ gradually decreases, and the resonantfrequency gradually increases by above changes of the t-air and thet-ink. Therefore, the ink quantity remained inside the ink tank or theink consumption quantity can be detected. The equation (7) depends onlyon the density of the liquid because of the assumption that the densityof the air is small compare to the density of the liquid so that thedensity of the air can be ignored.

[0269] When the actuator 106 is provided on the ink cartridgesubstantially perpendicular to the ink surface, the status can beexpressed as the equivalent circuit, not shown in the figure, on whichthe region, where the medium involved with the vibration of the actuator106 is ink only, and the region, where the medium involved with thevibration of the actuator 106 is gas, can be expressed as parallelcircuit. If let the area of the region where the medium involved withthe vibration of the actuator 106 is ink only as Sink, and let the areaof the region where the medium involved with the vibration of theactuator 106 is gas only as Sair, the following equation (9) can beobtained. $\begin{matrix}{{1/M^{\prime}} = {{{{1/M^{\prime}}{air}} + {{1/M^{\prime}}{ink}}} = {{S\quad {{air}/\left( {\rho \quad {air}*t\text{-}{air}} \right)}} + {S\quad {{ink}/\left( {\rho \quad {ink}*t\text{-}{ink}} \right)}}}}} & (9)\end{matrix}$

[0270] The equation (9) can be applied when the ink is not held in thecavity of the actuator 106. The case when the ink is held in the cavitycan be calculated using the equation (7), (8), and (9).

[0271] In the case when the thickness of the base plate 178 is thick,that is, the depth of the cavity 162 is deep and d is comparativelyclose to the thickness of the medium t-ink-max, or in the case whenusing actuator having a very small vibrating region compared to heightof the liquid container, the actuator does not detect the process of thegradual decrease of the ink but actually detects whether the ink levelis higher or lower than the mounting position of the actuator. In otherwords, the actuator detects the existence of the ink at the vibratingregion of the actuator. For example, the curve Y in FIG. 24(A) shows therelationship between the ink quantity in the ink tank and the resonantfrequency fs of the vibrating section when the vibrating section issmall circular shape. The curve Y shows that the resonant frequency fsof the ink and the vibrating section changes extremely during the rangeof change of ink quantity Q, which corresponds to the status before andafter the ink level in the ink tank passes the mounting position of theactuator. By this changes of the resonant frequency fs, it can bedetected whether the ink quantity remained in the ink tank is more thanthe predetermined quantity.

[0272] The method of using the actuator 106 for detecting the existenceof the liquid is more accurate than the method which calculates thequantity of ink consumption by the software because the actuator 106detects the existence of the ink by directly contacting with the liquid.Furthermore, the method using an electrode to detects the existence ofthe ink by conductivity is influenced by the mounting position to theliquid container and the ink type, but the method using the actuator 106to detects the existence of the liquid does not influenced by themounting position to the liquid container and the ink type. Moreover,because both of the oscillation and detection of the existence of theliquid can be done by the single actuator 106, the number of the sensormounted on the liquid container can be reduced compare to the methodusing separate sensor for oscillation and the detection of the existenceof the liquid. Therefore, the liquid container can be manufactured at alow price. Furthermore, the sound generated by the actuator 106 duringthe operation of the actuator 106 can be reduced by setting thevibrating frequency of the piezoelectric layer 160 out of the audiofrequency.

[0273]FIG. 24(B) shows the relationship between the density of the inkand the resonant frequency fs of the ink and the vibrating section ofthe curve Y shown in FIG. 24(A). Ink is used as an example of liquid. Asshown in FIG. 24(B), when ink density increases, the resonant frequencyfs decreases because the additional inertance increases. In other words,the resonant frequency fs are different with the types of the ink.Therefore, By measuring the resonant frequency fs, it can be confirmedwhether the ink of a different density has been mixed together duringthe re-filling of the ink to the ink tank.

[0274] Therefore, the actuator 106 can distinguish the ink tank whichcontains the different type of the ink.

[0275] The condition when the actuator 106 can accurately detects thestatus of the liquid will be explained in detail in following. The caseis assumed that the size and the shape of the cavity is designed so thatthe liquid can be remained in the cavity 162 of the actuator 106 evenwhen the liquid inside the liquid container is empty. The actuator 106can detect the status of the liquid even when the liquid is not filledin the cavity 162 if the actuator 106 can detect the status of theliquid when the liquid is filled in the cavity 162.

[0276] The resonant frequency fs is a function of the inertance M. Theinertance M is a sum of the inertance of the vibrating section Mact andthe additional inertance M′. Here, the additional inertance M′ has therelationship with the status of the liquid. The additional inertance M′is a quantity of a virtual increase of a mass of the vibrating sectionby the effect of the medium existed around the vibrating section. Inother words, the additional inertance M′ is the amount of increase ofthe mass of the vibrating section which is increased by the vibration ofthe vibrating section that virtually absorbs the medium.

[0277] Therefore, when the M′cav is larger than the M′max in theequation (4), all the medium which is virtually absorbed is the liquidremained in the cavity 162. Therefore, the status when the M′cav islarger than the M′max is same with the status that the liquid containeris fill with liquid. The resonant frequency fs does not change becausethe M′ does not change in this case. Therefore, the actuator 106 cannotdetect the status of the liquid in the liquid container.

[0278] On the other hand, if the M′cav is smaller than the M′max in theequation (4), the medium which is virtually absorbed is the liquidremained in the cavity 162 and the gas or vacuum in the liquidcontainer. In this case, because the M′ changes, which is different withthe case when the liquid is filled in the liquid container, the resonantfrequency fs changes. Therefore, the actuator 106 can detect the statusof the liquid in the liquid container.

[0279] The condition whether the actuator 106 can accurately detect thestatus of the liquid is that the M′cav is smaller than the M′max whenthe liquid is remained in the cavity 162 of the actuator 106, and theliquid container is empty. The condition M′max>M′cav, on which theactuator 106 can accurately detect the status of the liquid, does notdepend on the shape of the cavity 162.

[0280] Here, the M′cav is the mass of the liquid of the volume which issubstantially equal to the volume of the cavity 162. Therefore, thecondition, which can detect the status of the liquid accurately, can beexpressed as the condition of the volume of the cavity 162 from theinequality M′max>M′cav. For example, if let the radius of the opening161 of the circular shaped cavity 162 as “a” and the thickness of thecavity 162 as “d”, then the following inequality can be obtained.

M′max>ρ*d/πa²  (10)

[0281] By expanding the inequality (10), the following condition can beobtained.

a/d>3*π/8  (11)

[0282] The inequality (10) and (11) are valid only when the shape of thecavity 162 is circular. By using the equation when the M′max is notcircular and substituting the area πa² with its area, the relationshipbetween the dimension of the cavity such as a width and a length of thecavity and the depth can be derived.

[0283] Therefore, if the actuator 106 has the cavity 162 which has theradius of the opening 161 “a” and the depth of the cavity “d” thatsatisfy the condition shown in inequality (11), the actuator 106 candetect the liquid status without malfunction even when the liquidcontainer is empty and the liquid is remained in the cavity 162.

[0284] Because the additional inertance influences the acousticimpedance characteristic, it can be said that the method of measuringthe counter electromotive force generated in actuator 106 by residualvibration measures at least the change of the acoustic impedance.

[0285] Furthermore, according to the present embodiment, the actuator106 generates the vibration, and the actuator 106 itself measures thecounter electromotive force in actuator 106 which is generated by theresidual vibration remained after the vibration of the actuator 106.However, it is not necessary for the vibrating section of the actuator106 to provide the vibration to the liquid by the vibration of theactuator 106 itself which is generated by the driving voltage. Even thevibrating section itself does not oscillates, the piezoelectric layer160 deflects and deforms by vibrates together with the liquid, whichcontacts with the vibrating section with some range. This residualvibration generates the counter electromotive force voltage in thepiezoelectric layer 160 and transfer this counter electromotive forcevoltage to the upper electrode 164 and the lower electrode 166. Thestatus of the liquid can be detected using this phenomenon For example,in case of the ink jet recording apparatus, the status of the ink tankor the ink contained inside the ink tank can be detected using thevibration around the vibrating section of the actuator which isgenerated by the vibration generated by the reciprocating motion of thecarriage to scanning the print head during the printing operation.

[0286] FIGS. 25(A) and 25(B) shows a waveform of the residual vibrationof the actuator 106 and the measuring method of the residual vibration.The change of the ink level at the level of the mounting position of theactuator 106 in the ink cartridge can be detected by the change in thefrequency or the amplitude of the residual vibration remained after theoscillation of the actuator 106. In FIGS. 25(A) and 25(B), the verticalaxis shows the voltage of the counter electromotive force generated bythe residual vibration of the actuator 106, and the horizontal axisshows the time. By the residual vibration of the actuator 106, thewaveform of the analog signal of the voltage generates as shown in FIGS.25(A) and 25(B). Then, the analog signal is converted to a digitalnumerical value corresponding to the frequency of the signal.

[0287] In the example sown in FIGS. 25(A) and 25(B), the existence ofthe ink is detected by measuring the time during the generation of thefour numbers of pulses from the fourth pulse to the eighth pulse of theanalog signal.

[0288] In detail, after the actuator 106 oscillates, the number of thetimes when the analog signal get across the predetermined referencevoltage form the low voltage side to the high voltage side. The digitalsignal is set to be high while the analog signal becomes fourth countsto the eighth counts, and the time during fourth counts to the eighthcounts is measured by predetermined clock pulse.

[0289]FIG. 25(A) shows the waveform when the ink level is above thelevel of the mounting position of the actuator 106. FIG. 25(B) shows thewaveform when the ink level is below the level of the mounting positionof the actuator 106. Comparing the FIGS. 25(A) and 25(B), the time ofthe FIG. 25(A) during the fourth counts to the eighth counts is longerthan the time of the FIG. 25(B). In other words, depends on theexistence of the ink, the time from the fourth counts to the eighthcounts is different. By using this difference of the time, theconsumption status of the ink can be detected. The reason to count theanalog signal from the fourth counts is to start the measurement of thetime after the vibration of the actuator 106 becomes stable. It is onlyone of the example of starting the measurement from fourth counts, butmeasurement can be started from the desired counts.

[0290] The signals from the fourth counts to the eighth counts aredetected, and the time from the fourth counts to the eighth counts ismeasured by the predetermined clock pulse. By this measurement, theresonant frequency can be obtained. The clock pulse is prefer to be apulse having a same clock with the clock for controlling such as thesemiconductor memory device which is mounted on the ink cartridge. Itdoes not necessary to measure the time until the eighth counts, but thetime until the desired counts can be measured. In FIG. 25, the time fromthe fourth counts to the eighth counts is measured, however, the timeduring the different interval of the counts also can be detectedaccording to the circuit configuration which detects the frequency.

[0291] For example, when the ink quality is stable and the fluctuationof the amplitude of the peak is small, the resonant frequency can bedetected by detecting the time from the fourth counts to the sixthcounts to increase the speed of detection. Moreover, when the inkquality is unstable and the fluctuation of the amplitude of the pulse islarge, the time from the fourth counts to the twelfth counts can bedetected to detect the residual vibration accurately.

[0292] Furthermore, as other embodiments, the wave number of the voltagewaveform of the counter electromotive force during the predeterminedperiod can be counted. More specifically, after the actuator 106oscillates, the digital signal is set to be high during thepredetermined period, and the number of the times when the analog signalis get across the predetermined reference voltage from the low voltageside to the high voltage side is counted. By measuring the count number,the existence of the ink can be detected.

[0293] Furthermore, it can be known by comparing FIG. 25(A) with FIG.25(B), the amplitude of the waveform of the counter electromotive forceis different when the ink is filled in the ink cartridge and when theink is not existed in the ink cartridge. Therefore, the ink consumptionstatus in the ink cartridge can be detected by measuring the amplitudeof the waveform of the counter electromotive force without calculatingthe resonant frequency. More specifically, for example, a referencevoltage is set between the peak point of the waveform of the counterelectromotive force of the FIG. 25(A) and the peak point of the waveformof the counter electromotive force of the FIG. 25(B). Then, after theactuator 106 oscillates, set the digital signal to be high at thepredetermined time. Then, if the waveform of the counter electromotiveforce get across the reference voltage, it can be judged that there isno ink in the ink cartridge. If the waveform of the counterelectromotive force does not get across the reference voltage, it can bejudged that there is ink in the ink cartridge.

[0294]FIG. 26 shows the manufacturing method of the actuator 106. Aplurality of the actuators 106, four numbers in the case of the FIG. 26,are formed as one body. The actuator 106 shown in FIG. 27 ismanufactured by cutting the plurality of actuator 106, which is formedin one body as shown in FIG. 26, at each of the actuator 106. If theeach of the piezoelectric elements of the each of the plurality of theactuator 106, which is formed in one body as shown in FIG. 26, arecircular shape, the actuator 106 shown in FIG. 22 can be manufactured bycutting the actuator 106, which is formed as one body, at each ofactuator 106. By forming a plurality of the actuator 106 in one body, aplurality of actuator 106 can be manufactured effectively at the sametime, and also the handling during the transportation becomes easy.

[0295] The actuator 106 has a thin plate or a vibrating plate 176, abase plate 178, an elastic wave generating device or piezoelectricelement 174, a terminal forming member or an upper electrode terminal168, and a terminal forming member or a lower electrode terminal 170.The piezoelectric element 174 includes a piezoelectric vibrating plateor a piezoelectric layer 160, an upper electrode 164, and a lowerelectrode 166. The vibrating plate 176 is formed on the top surface ofthe base plate 178, and the lower electrode 166 is formed on the topsurface of the vibrating plate 176. The piezoelectric layer 160 isformed on the top surface of the lower electrode 166, and the upperelectrode 164 is formed on the top surface of the piezoelectric layer160. Therefore, the main portion of the piezoelectric layer 160 isformed by sandwiching the main portion of the piezoelectric layer 160 bythe main portion of the upper electrode 164 and the main portion of thelower electrode 166 from top side and from bottom side.

[0296] A plurality of the piezoelectric element 174, four numbers in thecase of FIG. 26, is formed on the vibrating plate 176. The lowerelectrode 166 is formed on the top surface of the vibrating plate 176.The piezoelectric layer 160 is formed on the top surface of the lowerelectrode 166, and the upper electrode 164 is formed on the top surfaceof the piezoelectric layer 160. The upper electrode terminal 168 and thelower electrode terminal 170 are formed on the end portion of the upperelectrode 164 and the lower electrode 166. The four numbers of theactuator 106 are used separately by cutting each of the actuator 106separately.

[0297]FIG. 27 shows a cross-section of a part of the actuator 106. Thethrough hole 178 a is formed on the face of the base plate 178 whichfaces with the piezoelectric element 174. The through hole 178 a issealed by the vibrating plate 176. The vibrating plate 176 is formed bythe material which has electric insulating characteristic such asalumina and zirconium oxide and also possible to be deformedelastically. The piezoelectric element 174 is formed on the vibratingplate 176 to face with the through hole 178 a. The lower electrode 166is formed on the surface of the vibrating plate 176 so as to be extendedto the one direction, left direction in FIG. 28, from the region of thethrough hole 178 a. The upper electrode 164 is formed on the surface ofthe piezoelectric layer 160 so as to be extended to the oppositedirection of the lower electrode 166, which is right direction in FIG.28, from the region of the through hole 178 a. Each of the upperelectrode terminal 168 and the lower electrode terminal 170 is formed onthe surface of the each of supplementary electrode 172 and the lowerelectrode 166, respectively. The lower electrode terminal 170 with thelower electrode 166 electrically, and the upper electrode terminal 168contacts with the upper electrode 164 electrically through thesupplementary electrode 172 to deliver a signal between thepiezoelectric element and the outside of the actuator 106. The upperelectrode terminal 168 and the lower electrode terminal 170 has a heighthigher than the height of the piezoelectric element which is the sum ofthe height of the electrodes and the piezoelectric layer.

[0298]FIG. 29 shows the manufacturing method of the actuator 106 shownin FIG. 26. First, a through hole 940 a is formed on a green sheet 940by perforating the green sheet 940 by a press or laser processing. Thegreen sheet 940 becomes the base plate 178 after the burning process.The green sheet 940 is formed by the material such as ceramic material.Then, a green sheet 941 is laminated on the surface of the green sheet940. The green sheet 941 becomes the vibrating plate 176 after theburning process. The green sheet 941 is formed by the material such aszirconium oxide. Then, a conductive layer 942, the piezoelectric layer160, and a conductive layer 944 is formed on the surface of the greensheet 941 sequentially by the method such as printing. The conductivelayer 942 becomes the lower electrode 166, and the conductive layer 944becomes the upper electrode 164 after the burning process.

[0299] Next, the green sheet 940, the green sheet 941, the conductivelayer 942, the piezoelectric layer 160, and the conductive layer 944 aredried and burned. The spacer member 947 and 948 are provided on thegreen sheet 941 to raising the height of the upper electrode terminal168 and the lower electrode terminal 170 to be higher than thepiezoelectric element. The spacer member 947 and 948 is formed byprinting the same material with the green sheet 940 and 941 or bylaminating the green sheet on the green sheet 941. By this spacer member947 and 948, the quantity of the material of the upper electrodeterminal 168 and the lower electrode terminal 170, which is a noblemetal, can be reduced. Moreover, because the thickness of the upperelectrode terminal 168 and the lower electrode terminal 170 can bereduced, the upper electrode terminal 168 and the lower electrodeterminal 170 can be accurately printed to be a stable height.

[0300] If a connection part 944′, which is connected with the conductivelayer 944, and the spacer member 947 and 948 are formed at the same timewhen the conductive layer 942 is formed, the upper electrode terminal168 and the lower electrode terminal 170 can be easily formed and firmlyfixed. Finally, the upper electrode terminal 168 and the lower electrodeterminal 170 are formed on the end region of the conductive layer 942and the conductive layer 944. During the forming of the upper electrodeterminal 168 and the lower electrode terminal 170, the upper electrodeterminal 168 and the lower electrode terminal 170 are formed to beconnected with the piezoelectric layer 160 electrically.

[0301]FIG. 30 shows the further other embodiment of the ink cartridge ofthe present invention. In the ink cartridge shown in FIG. 30, inkabsorbing member 74 is provided in the container 1 to face to thethrough hole 1 c, which is provided inside the container 1, as a wavepreventing wall. The actuator 70 is fixed to the bottom of the container1 to face to the through hole 1 c. the ink absorbing member 74 preventsthe wave or bubbles of ink inside the ink cartridge to enter into thethrough hole 1 c. The ink absorbing member thereby prevents the wave orbubbles of ink to move close to the actuator 70 and attach to theactuator 70.

[0302] The ink absorbing member 74 is designed such that the holediameter of the porous part 74 b around the ink supply port 2 is smallerthan the hole diameter of the porous part 74 a around the actuator 70.Furthermore, the ink absorbing member 74 is designed such that thecapillary force of the porous part 74 b around the ink supply port 2 issmaller than the capillary force in a degree which holds ink.

[0303] Thereby, if the ink absorbing member 74 exposes from ink byconsuming of ink inside the container 1, ink in the ink absorbing member74 flows out from the ink absorbing member 74 by its own weight to theink supply port 2. If all the ink inside the container 1 consumed up,the ink absorbing member 74 absorbs the ink remained in the through hole1 c by the capillary force. Therefore, ink is drained from the concavepart of the through hole 1 c. Therefore, because the residual vibrationof the actuator 70 changes at the ink end status, the timing of the inkend can be further reliably detected.

[0304] Therefore, the ink absorbing member 74 can protect the actuator70 from the wave of ink and also absorbs the ink remained in the throughhole 1 c to improve the accuracy of the ink end detection of theactuator 106.

[0305]FIG. 31 shows further other embodiment of the ink cartridge of thepresent invention. FIG. 31(A) is a cross sectional view of the bottompart of the ink cartridge of the present embodiment. The ink cartridgeof the present embodiment has a through hole 1 c on the bottom face 1 aof the container 1, which contains ink. The bottom part of the throughhole 1 c is closed by the actuator 650 and forms an ink storing part.The ink absorbing member 78 is provided around the inside the throughhole 1 c which is provided inside the container 1 and around the throughhole 1 c as a wave preventing wall. The ink absorbing member 78 has aink absorbing member 78 a which is provided inside the through hole 1 cand the ink absorbing member 78 b which is provided around the throughhole 1 c.

[0306]FIG. 31(B) shows a detailed cross section of the actuator 650 andthe through hole 1 c shown in FIG. 31(A). FIG. 31(C) shows a plan viewof the actuator 650 and the through hole 1 c shown in FIG. 31(B). Theactuator 650 has a vibrating plate 72 and a piezoelectric element 73which is fixed to the vibrating plate 72. The vibrating plate 72 can beelastically deformed and is ink resistant. In the present embodiment,the shape of the piezoelectric element 73 and the through hole 1 c islong and narrow rectangular, and both ends of which is circular shape.

[0307]FIG. 32 shows other embodiment of the through hole 1 c. In each ofFIG. 32(A), (B), and (C), the left hand side of the figure shows thestatus that there is no ink K in the through hole 1 c, and the righthand side of the figure shows the status that ink K is remained in thethrough hole 1 c. In the embodiment of FIG. 31, the side face of thethrough hole 1 c is formed as the vertical wall. In FIG. 32(A), the sideface id of the through hole 1 c is slanted in vertical direction andopens with expanding to the outside. In FIG. 32(B), a stepped portion 1e and 1 f are formed on the side face of the through hole 1 c. Thestepped portion 1 f, which is provided above the stepped portion 1 e, iswider than the stepped portion 1 e. In FIG. 32(C), the through hole 1 chas a groove 1 g that extends to the direction in which ink is easilydischarged, that is, the direction to a ink supply port 2.

[0308] A wave preventing wall, not shown in the figure, is provided inthe container 1 such that the wave preventing wall faces to the actuator650.

[0309] According to the shape of the through hole 1 c shown in FIG.32(A) to (C), the quantity of ink K in the ink storing part can bereduced. Therefore, because the M′ cav can be smaller than the M′maxexplained in FIGS. 22 and 23, the vibration characteristic of theactuator 650 at the time of the ink end status can be greatly differentwith the vibration characteristic when enough quantity of ink K forprinting is remained in the container 1, and thus the ink end status canbe reliably detected.

[0310]FIG. 33(A) and (B) is a slant view of the further other embodimentof the actuator. FIG. 33(B) shows a part of a side cross section of theink cartridge, on which an actuator 670 of the embodiment shown in FIG.33(A) is mounted. In the present embodiment, the actuator 670 comprisesa concave part forming base plate 80 and a piezoelectric element 82. Theconcave part 81 is formed on the one side of the face of the concavepart forming base plate 80 by the technique such as etching, andpiezoelectric element 82 is mounted on the other side of the face of theconcave part forming base plate 80. The bottom portion of the concavepart 81 operates as a vibrating region within the concave part formingbase plate 80. Therefore, the vibrating region of the actuator 670 isdetermined by the periphery of the concave part 81. Furthermore, theactuator 670 has the similar structure with the structure of theactuator 106 shown in FIG. 22, in which the base plate 178 and thevibrating plate 176 is formed as one body. Therefore, the manufacturingprocess during the manufacturing an ink cartridge can be reduced, andthe cost for manufacturing an ink cartridge also can be reduced. Theactuator 670 has a size which can be embedded into the through hole 1 cprovided on the container 1. By this embedding process, the concave part81 can operates as the cavity. The actuator 106 shown in FIG. 22 can beformed to be embedded into through hole 1 c as actuator 670 shown inFIG. 33. Moreover, the wave preventing wall 1192 u is provided nearbythe concave part 81 in the container 1 such that the wave preventingwall 1192 u faces to the actuator 670.

[0311]FIG. 34 shows a slant view of the other embodiment of theactuator. The actuator 660 has packing 76 on the outside of the baseplate, which constitutes the actuator 660, or the through hole 1 c of amounting plate 72. Caulking holes 77 are formed on the outskirts of theactuator 660. The actuator 660 is fixed to the container 1 through thecaulking hole 77 with caulking.

[0312] Furthermore, also in the present embodiment, the wave preventingwall, not shown in the figure, can be provided nearby the packing 76such that the wave preventing wall faces to the actuator 670 as shown inFIG. 33(B). If the wave preventing wall, not shown in the figure, isform of a mesh or a material which pass through ink such as porousmaterial, the wave preventing wall can be previously mounted on theperiphery of the packing 76. If the wave preventing wall is the memberwhich pass through ink, the actuator 660 can detects ink. In this case,the wave preventing wall 1192 u is mounted on the ink cartridge togetherwith the actuator 670 as one body. Because the process of mounting thewave preventing wall on the ink cartridge is abbreviate, themanufacturing process is reduced, and the cycle time and cost ofmanufacturing the ink cartridge are reduced.

[0313]FIGS. 35A, 35B and 35C show plan views of the through hole 1 caccording to another embodiment. As shown respectively in FIGS. 35A, 35Band 35C, the plane shape of the through hole 1 c may be of arbitraryshapes such as circular, rectangular, and triangle shape as long as theelastic wave generating device is capable of being mounted thereto.

[0314]FIG. 36 shows a slant view of the configuration that forms theactuator 106 in one body as a mounting module 100. The module 100 ismounted on the predetermined position of the container 1 of an inkcartridge. The module 100 is constituted to detect the ink consumptionstatus in the container 1 by detecting at least the change of acousticimpedance of the ink liquid. The module 100 of the present embodimenthas a liquid container mounting member 101 for mounting the actuator 106to the container 1. The liquid container mounting member 101 has astructure which mounts a cylindrical part 116 that contains the actuator106 which oscillates by the driving signal on a base mount 102, the planof which is substantially rectangular. Because the module 100 isconstructed so that the actuator 106 of the module 100 can not becontact from outside when the module 100 is mounted on the inkcartridge, the actuator 106 can be protected from outside contact. Thetop side of the edge of the cylindrical part 116 is chamfered so thatthe cylindrical part 116 can be easily fit into the hole which is formedin the ink cartridge.

[0315]FIG. 37 shows an exploded view of the module 100 shown in FIG. 36to show the structure of the module 100. The module 100 includes aliquid container mounting member 101 made from a resin and apiezoelectric device mounting member 105 which has a plate 110 and aconcave part 113. Furthermore, the module 100 has a lead wire 104 a and104 b, actuator 106, and a film 108. Preferably, the plate 110 is madefrom a material which is difficult to be rust such as stainless orstainless alloy. The opening 114 is formed on the central part of thecylindrical part 116 and the base mount 102 which are included in theliquid container mounting member 101 so that the cylindrical part 116and the base mount 102 can contain the lead wire 104 a and 104 b. Theconcave part 113 is formed on the central part of the cylindrical part116 and the base mount 102 so that the cylindrical part 116 and the basemount 102 can contain the actuator 106, the film 108, and the plate 110.The actuator 106 is connected to the plate 110 through the film 108, andthe plate 110 and the actuator 106 are fixed to the liquid containermounting member 101. Therefore, the lead wire 104 a and 104 b, theactuator 106, the film 108 and the plate 110 are mounted on the liquidcontainer mounting member 101 as one body. Each of the lead wire 104 aand 104 b transfer a driving signal to piezoelectric layer by couplingwith the upper electrode and the lower electrode 166 of the actuator106, and also transfer the signal of resonant frequency detected by theactuator 106 to recording apparatus. The actuator 106 oscillatestemporally based on the driving signal transferred from the lead wire104 a and 104 b. The actuator 106 vibrates residually after theoscillation and generates a counter electromotive force by the residualvibration. By detecting the vibrating period of the waveform of thecounter electromotive force, the resonant frequency corresponding to theconsumption status of the liquid in the liquid container can bedetected. The film 108 bonds the actuator 106 and the plate 110 to sealthe actuator 106. The film 108 is preferably formed by such aspolyolefin and bonded to the actuator 106 and the plate 110 by heatsealing. By bonding the actuator 106 and the plate 110 with the film 108face with face, the unevenness of the bonding on location decreases, andthus the portion other than the vibrating plate does not vibrate.Therefore, the change of the resonant frequency before and after bondingthe actuator 106 to plate 110 is small.

[0316] The plate 110 is circular shape, and the opening 114 of the basemount 102 is formed in cylindrical shape. The actuator 106 and the film108 are formed in rectangular shape. The lead wire 104, the actuator106, the film 108, and the plate 110 can be attached to and removed fromthe base mount 102. Each of the base mount 102, the lead wire 104, theactuator 106, the film 108, and the plate 110 is arranged symmetric withrespect to the central axis of the module 100. Furthermore, each of thecenters of the base mount 102, the actuator 106, the film 108, and theplate 110 is arranged substantially on the central axis of the module100.

[0317] The opening 114 of the base mount 102 is formed such that thearea of the opening 114 is larger than the area of the vibrating regionof the actuator 106. The through hole 112 is formed on the center of theplate 110 where the vibrating section of the actuator 106 faces. Asshown in FIGS. 22 and 23, the cavity 162 is formed on the actuator 106,and both of the through hole 112 and the cavity 162 forms ink storingpart. The thickness of the plate 110 is preferably smaller than diameterof the through hole 112 to reduce the influence of the residual ink. Forexample, the depth of the through hole 112 is preferably smaller thanone third of the diameter of the through hole 112. The shape of thethrough hole 112 is substantially true circle and symmetric with respectto the central axis of the module 100. Furthermore, the area of thethrough hole 112 is larger than the area of opening of the cavity 162 ofthe actuator 106. The periphery of the shape of the cross-section of thethrough hole 112 can be tapered shape of stepped shape. The module 100is mounted on the side, top, or bottom of the container 1 such that thethrough hole 112 faces to the inside of the container 1. When the ink isconsumed, and the ink around the actuator 106 is exhausted, the resonantfrequency of the actuator 106 greatly changes. The change of the inklevel can thus be detected.

[0318]FIG. 38 shows the slant view of the other embodiments of themodule. The piezoelectric device mounting member 405 is formed on theliquid container mounting member 101 in the module 400 of the presentembodiment. The cylindrical part 403, which has a cylindrical shape, isformed on the base mount 102, which has a square shaped plan, the edgesof which are rounded, in the liquid container mounting member 401.Furthermore, the piezoelectric apparatus mounting member 405 includes aboard shaped element 405, which is set up on the cylindrical part 403,and a concave part 413. The actuator 106 is arranged on the concave part413 provided on the side face of the board shaped element 406. The topend of the board shaped element 406 is chamfered in predetermined angleso that the board shaped element is easy to fit into hole formed on theink cartridge when mounting the actuator 106 to ink cartridge.

[0319]FIG. 39 shows an exploded view of the module 400 shown in FIG. 38to show the structure of the module 400. As the module 100 shown in FIG.36, the module 400 includes a liquid container mounting member 401 and apiezoelectric device mounting member 405. The liquid container mountingmember 401 has the base mount 402 and the cylindrical part 403, and thepiezoelectric device mounting member 405 has the board shaped element406 and the concave part 413. The actuator 106 is connected to the plate410 and fixed to the concave part 413. The module 400 has a lead wire404 a and 404 b, actuator 106, and a film 408.

[0320] According to the present embodiment, the plate 410 is rectangularshape, and the opening 414 provided on the board shaped element 406 isformed in rectangular shape. The lead wire 404 a and 404 b, the actuator106, the film 408, and the plate 410 can be attached to and removed fromthe base mount 402. Each of the actuator 106, the film 408, and theplate 410 is arranged symmetric with respect to the central axis whichis extended to perpendicular direction to the plan of opening 414 andalso pass through the center of opening 414. Furthermore, each of thecenters of the actuator 106, the film 408, and the plate 410 is arrangedsubstantially on the central axis of the opening 414.

[0321] The through hole 412 provided on the center of the plate 410 isformed such that the area of the through hole 412 is larger than thearea of the opening of the cavity 162 of the actuator 106. The cavity162 of the actuator 106 and the through hole 412 together forms inkstoring part. The thickness of the plate 410 is preferably smaller thandiameter of the through hole 412. For example, the thickness of theplate 410 is smaller than one third of the diameter of the through hole412. The shape of the through hole 412 is substantially true circle andsymmetric with respect to the central axis of the module 400. The shapeof the cross-section of the periphery of the through hole 112 can betapered shape or stepped shape. The module 400 can be mounted on thebottom of the container 1 such that the through hole 412 is arrangedinside of the container 1. Because the actuator 106 is arranged insidethe container 1 such that the actuator 106 extends in the verticaldirection, the setting of the timing of the ink end can be easilychanged by changing the height of the mounting position of the actuator106 in the container 1 by changing the height of the base mount 402.

[0322]FIG. 40 shows the further other embodiment of the module. As themodule 100 shown in FIG. 36, the module 500 of FIG. 40 includes a liquidcontainer mounting member 501 which has a base mount 502 and acylindrical part 503. Furthermore, the module 500 further has a leadwire 504 a and 504 b, actuator 106, a film 508, and a plate 510. Theopening 514 is formed on the center of the base mount 502, which isincluded in the liquid container mounting member 501, so that the basemount 502 can contain the lead wire 504 a and 504 b. The concave part513 is formed on the cylindrical part 503 so that the cylindrical part503 can contain the actuator 106, the film 508, and the plate 510. Theactuator 106 is fixed to the piezoelectric device mounting member 505through the plate 510. Therefore, the lead wire 504 a and 504 b, theactuator 106, the film 508, and the plate 510 are mounted on the liquidcontainer mounting member 501 as one body. The cylindrical part 503, thetop face of which is slanted in vertical direction, is formed on thebase mount which has a square shaped plan and the edges of which arerounded. The actuator 106 is arranged on the concave part 513 which isprovided on the top surface of the cylindrical part 503 that is slantedin vertical direction.

[0323] The top end of the module 500 is slanted, and the actuator 106 ismounted on this slanted surface. Therefore, if the module 500 is mountedon the bottom or the side of the container 1, the actuator 106 slants inthe vertical direction of the container 1. The slanting angle of the topend of the module 500 is substantially between 30 degree and 60 degreewith considering the detecting performance.

[0324] The module 500 is mounted on the bottom or the side of thecontainer 1 so that the actuator 106 can be arranged inside thecontainer 1. When the module 500 is mounted on the side of the container1, the actuator 106 is mounted on the container 1 such that the actuator106 faces the upside, downside, or side of the container 1 withslanting. When the module 500 is mounted on the bottom of the container1, the actuator 106 is preferable to be mounted on the container 1 suchthat the actuator 106 faces to the ink supply port side of the container1 with slanting.

[0325]FIG. 41 shows a cross-sectional view around the bottom of thecontainer 1 when the module 100 shown in FIG. 36 is mounted on thecontainer 1. The module 100 is mounted on the container 1 so that themodule 100 penetrates through the side wall of the container 1. TheO-ring 365 is provided on the connection face of between the side wallof the container 1 and the module 100 to seal between the module 100 andthe container 1. The module 100 is preferable to include the cylindricalpart as explained in FIG. 36 so that the module 100 can be sealed by theO-ring. By inserting the top end of the module 100 inside the container1, ink in the container 1 contacts with the actuator 106 through thethrough hole 112 of the plate 110. Because the resonant frequency of theresidual vibration of the actuator 106 is different depends on whetherthe circumference of the vibrating section of the actuator 106 is liquidor gas, the ink consumption status can be detected using the module 100.Furthermore, not only the module 100 can be mounted on the container 1and detect the existence of ink, but also the module 400 shown in FIG.38, module 500 shown in FIG. 40, or the module 700A and 700B shown inFIG. 42, and a mold structure 600 can be mounted on the container 1 anddetect the existence of the ink.

[0326]FIG. 42(A) shows the cross section of the ink container whenmounting module 700B on the container 1. The present embodiment uses amodule 700B as an example of a mounting structure. The module 700B ismounted on the container 1 such that the liquid container mountingmember 360 protrude into the inside of the A through hole 370 is formedin the mounting plate 350, and the through hole 370 faces to thevibrating section of the actuator 106. Furthermore, a hole 382 is formedon the bottom wall of the module 700B, and a piezoelectric devicemounting member 363 is formed. The actuator 106 is arranged to close theone of the face of the hole 382. Therefore, ink contacts with thevibrating plate 176 through the hole 382 of the piezoelectric devicemounting member 363 and the through hole 370 of the mounting plate 350.The hole 382 of the piezoelectric device mounting member 363 and thethrough hole 370 of the mounting plate 350 together forms an ink storingpart. The piezoelectric device mounting member 363 and the actuator 106are fixed by the mounting plate 350 and the film material. The sealingstructure 372 is provided on the connection part of the liquid containermounting member 360 and the container 1. The sealing structure 372 canbe formed by the plastic material such as synthetic resin or O-ring. InFIG. 42(A), the module 700B and the container 1 is separate body,however, the piezoelectric device mounting member can be constituted bya part of the container 1 as shown in FIG. 42(B).

[0327] The module 700B shown in FIG. 42 does not need to embed the leadwire into the module as shown in FIG. 36 to FIG. 40. Therefore, theforming process becomes simple. Also, the exchange of the module 700Bbecomes possible so that the recycling of the module 700B also becomespossible.

[0328] There is possibility that the actuator 106 malfunctions by thecontact of the ink which is dropped from a top face or a side face ofthe container 1 with the actuator 106, the ink of which is attached tothe top face or the side face of the container 1 when the ink cartridgeis shaken. However, because the liquid container mounting member 360 ofthe module 700B protrudes into the inside of the container 1, theactuator 106 does not malfunction by the ink dropped from the top faceor the side face of the container 1.

[0329] Furthermore, the module 700B is mounted on the container 1 sothat only part of the vibrating plate 176 and the mounting plate 350 arecontact with ink inside of the container 1 in the embodiment of FIG.42(A). The embedding of the electrode of the lead wire 104 a, 104 b, 404a, 404 b, 504 a, and 504 shown in FIG. 36 to FIG. 40 into the modulebecomes unnecessary for the embodiment shown in FIG. 42(A). Therefore,the forming process becomes simple. Also, the exchange of the actuator106 becomes possible so that the recycling of the actuator 106 alsobecomes possible.

[0330]FIG. 42(B) shows the cross section of the ink container whenmounting actuator 106 on the container 1. A protecting member 361 ismounted on the container separately with the actuator 106 in the inkcartridge of the embodiment shown in FIG. 42(B). Therefore, theprotecting member 361 and the actuator 106 is not one body as a module,and the protecting member 361 thus can protect the actuator 106 not tobe contact by the user. A hole 380 which is provide on the front face ofthe actuator 106 is arranged on the side wall of the container 1. Theactuator 106 includes the piezoelectric layer 160, the upper electrode164, the lower electrode 166, the vibrating plate 176, and the mountingplate 350. The vibrating plate 176 is formed on the mounting plate 350,and the lower electrode 166 is formed on the vibrating plate 176. Thepiezoelectric layer 160 is formed on the top face of the lower electrode166, and the upper electrode 164 is formed on the top face of thepiezoelectric layer 160.

[0331] Therefore, the main portion of the piezoelectric layer 160 isformed by sandwiching the main portion of the piezoelectric layer 160 bythe main portion of the upper electrode 164 and the lower electrode 166from top and bottom. The circular portion, which is a main portion ofeach of the piezoelectric layer 160, the upper electrode 164, and thelower electrode 166, forms a piezoelectric element. The piezoelectricelement is formed on the vibrating plate 176. The vibrating region ofthe piezoelectric element and the vibrating plate 176 constitutes thevibrating section, on which the actuator 106 actuary vibrates. A throughhole 370 is provided on the mounting plate 350. Furthermore, a hole 380is formed on the side wall of the container 1.

[0332] Therefore, ink contacts with the vibrating plate 176 through thehole 380 of the container 1 and the through hole 370 of the mountingplate 350. The hole 380 of the container land the through hole 370 ofthe mounting plate 350 together forms ink storing part.

[0333] Moreover, because the actuator 106 is protected by the protectingmember 361, the actuator 106 can be protected form the outside contact.The base plate 178 shown in FIG. 22 can be used instead of the mountingplate 350 in the embodiment shown in FIG. 42(A) and (B).

[0334]FIG. 42(C) shows an embodiment that comprises a mold structure 600which includes the actuator 106. In the present embodiment, a moldstructure 600 is used as one example of the mounting structure. The moldstructure 600 has the actuator 106 and a mold member 364. The actuator106 and the mold member 364 are formed in one body. The mold member 364is formed by a plastic material such as silicon resin. The mold member364 includes a lead wire 362 in its inside. The mold member 364 isformed so that the mold member 364 has two legs extended from theactuator 106. The end of the two legs of the mold member 364 are formedin a shape of hemisphere to liquid tightly fix the mold member 364 withcontainer 1. The mold member 364 is mounted on the container 1 such thatthe actuator 106 protrudes into the inside of the container 1, and thevibrating section of the actuator 106 contacts with ink inside thecontainer 1. The upper electrode 164, the piezoelectric layer 160, andthe lower electrode 166 of the actuator 106 are protected from ink bythe mold member 364.

[0335] Because the mold structure 600 shown in FIG. 42 does not need thesealing structure 372 between the mold member 364 and the container 1,the leaking of ink from the container 1 can be reduced. Moreover,because the mold structure 600 has a form that the mold structure 600does not protrude from the outside of the container 1, the moldstructure 600 can protect the actuator 106 from the outside contact.There is possibility that the actuator 106 malfunctions by the contactof the ink which is dropped from a top face or a side face of thecontainer 1 with the actuator 106, the ink of which is attached to thetop face or the side face of the container 1 when the ink cartridge isshaken. Because the mold member 364 of the mold structure 600 protrudesinto the inside of the container 1, the actuator 106 does notmalfunction by the ink dropped from the top face or the side face of thecontainer 1.

[0336]FIG. 43 shows an embodiment of an ink cartridge and an ink jetrecording apparatus which uses the actuator 106 shown in FIG. 22. Aplurality of ink cartridges 180 is mounted on the ink jet recordingapparatus which has a plurality of ink introducing members 182 and aholder 184 each corresponding to the each of ink cartridge 180,respectively. Each of the plurality of ink cartridges 180 containsdifferent types of ink, for example, different color of ink. Theactuator 106, which detects at least acoustic impedance, is mounted onthe each of bottom of the plurality of ink cartridge 180. The residualquantity of ink in the ink cartridge 180 can be detected by mounting theactuator 106 on the ink cartridge 180.

[0337] Furthermore, the wave preventing wall, not shown in the figure,is provided inside the ink cartridge 180 such that the wave preventingwall faces to the actuator 106.

[0338]FIG. 44 shows a detail around the head member of the ink jetrecording apparatus. The ink jet recording apparatus has an inkintroducing member 182, a holder 184, a head plate 186, and a nozzleplate 188. A plurality of nozzle 190, which jet out ink, is formed onthe nozzle plate 188. The ink introducing member 182 has an air supplyhole 181 and an ink introducing inlet 183. The air supply hole 181supplies air to the ink cartridge 180. The ink introducing inlet 183introduces ink from the ink cartridge 180. The ink cartridge 180 has anair introducing inlet 185 and an ink supply port 187. The airintroducing inlet 185 introduces air from the air supply hole 181 of theink introducing member 182. The ink supply port 187 supplies ink to theink introducing inlet 183 of the ink introducing member 182. Byintroducing air from the ink introducing member 182 to the ink cartridge180, the ink cartridge 180 accelerates the supply of ink from the inkcartridge 180 to the ink introducing member 182.

[0339] Furthermore, the wave preventing wall, not shown in the figure,is provided inside the ink cartridge 180 such that the wave preventingwall faces to the actuator 106.

[0340]FIG. 45 shows other embodiment of the ink cartridge 180 shown inFIG. 44. The actuator 106 is mounted on the bottom face 194 a, which isformed to be slanted in vertical direction, of the ink cartridge 180Ashown in the FIG. 45(A). A wave preventing wall 1192 v is provided onthe position where has the predetermined height from the bottom face ofthe inside the container 194 and also faces to the actuator 106 insidethe container 194 of the ink cartridge 180. Because the actuator 106 ismounted on the container 194 slanted in vertical direction, the drainageof ink can be improved.

[0341] A gap, which is filled with ink, is formed between the actuator106 and the wave preventing wall 1192 v. The gap between the wavepreventing wall 1192 v and the actuator 106 does not hold ink bycapillary force. When the container 194 is rolled, ink wave is generatedinside the container 194 by the waving, and there is possibility thatthe actuator 106 malfunctions by detecting gas or an air bubble causedby the shock of the ink wave. By providing the wave preventing wall 1192v, ink wave around the actuator 106 can be prevented so that themalfunction of the actuator 106 can be prevented.

[0342] The actuator 106 of the ink cartridge 180B shown in FIG. 45(B) ismounted on the side wall of the supply port of the container 194. Theactuator 106 can be mounted on the side wall or bottom face of thecontainer 194 if the actuator 106 is mounted nearby the ink supply port187. The wave preventing wall 1192W is provided nearby the ink supplyport 187 inside the container 194 such that the wave preventing wall1192W faces to the actuator 106. The wave preventing wall 1192 w isformed in L-shape to effectively prevent the wave of ink. Moreover, theactuator 106 is preferably mounted on the center of the width directionof the container 194. Because ink is supplied to the outside through theink supply port 187, ink and actuator 106 reliably contacts until thetiming of the ink near end by providing the actuator 106 nearby the inksupply port 187. Therefore, the actuator 106 can reliably detect thetiming of the ink near end.

[0343] Furthermore, by providing the actuator 106 nearby the ink supplyport 187, the setting position of the actuator 106 to the connectionpoint on the carriage on the ink container becomes reliable during themounting of the ink container on the cartridge holder of the carriage.It is because the reliability of coupling between the ink supply portwith the ink supply needle is most important during the coupling of theink container and the carriage. If there is even a small gap, the tip ofthe ink supply needle will be hurt or a sealing structure such as O-ringwill be damaged so that the ink will be leaked. To prevent this kind ofproblems, the ink jet printer usually has a special structure that canaccurately positioning the ink container during the mounting of the inkcontainer on the carriage. Therefore, the positioning of the actuator106 becomes reliable by arranging the actuator nearby the ink supplyport. Furthermore, the actuator 106 can be further reliably positionedby mounting the actuator 106 at the center of the width direction of thecontainer 194. It is because the waving is the smallest when the inkcontainer rolls along an axis, the center of which is center line of thewidth direction, during the mounting of the ink container on the holder.

[0344]FIG. 46 shows further other embodiment of the ink cartridge 180.FIG. 46(A) shows a cross section of an ink cartridge 180C, and FIG.46(B) shows a cross section which enlarges the side wall 194 b of an inkcartridge 180C shown in FIG. 46(A). FIG. 46(C) shows perspective viewfrom the front of the side wall 194 b of the ink cartridge 180C. Thesemiconductor memory device 7 and the actuator 106 are formed on thesame circuit board 610 in the ink cartridge 180C. As shown in FIG.46(A), the wave preventing wall 1192 x is provided inside the container194 such that the wave preventing wall 1192 x faces to the actuator 700.As shown in FIG. 46(B) and (C), the semiconductor memory device 7 isformed on the upper side of the circuit board 610, and the actuator 106is formed on the lower side of the semiconductor memory device 7 on thesame circuit board 610. A different-type O-ring 614 is mounted on theside wall 194 b such that the different-type O-ring 614 surrounds theactuator 106. A plurality of caulking part 616 is formed on the sidewall 194 b to couple the circuit board 610 with the container 194. Bycoupling the circuit board 610 with the container 194 using the caulkingpart 616 and pushing the different-type O-ring 614 to the circuit board610, the vibrating region of the actuator 106 can contacts with ink, andat the same time, the inside of the ink cartridge is sealed from outsideof the ink cartridge.

[0345] A terminals 612 are formed on the semiconductor memory device 7and around the semiconductor memory device 7. The terminal 612 transferthe signal between the semiconductor memory device 7 and outside the inkjet recording apparatus. The semiconductor memory device 7 can beconstituted by the semiconductor memory which can be rewritten such asEEPROM. Because the semiconductor memory device 7 and the actuator 106are formed on the same circuit board 610, the mounting process can befinished at one time during mounting the semiconductor memory device 7and the actuator 106 on the ink cartridge 180C. Moreover, the workingprocess during the manufacturing of the ink cartridge 180C and therecycling of the ink cartridge 180C can be simplified. Furthermore, themanufacturing cost of the ink cartridge 180C can be reduced because thenumbers of the parts can be reduced.

[0346] The actuator 106 detects the ink consumption status inside thecontainer 194. The semiconductor memory device 7 stores the informationof ink such as residual quantity of ink detected by the actuator 106.That is, the semiconductor memory device 7 stores the informationrelated to the characteristic parameter such as the characteristic ofink and the ink cartridge used for the actuator 106 when detecting theink consumption status. The semiconductor memory device 7 previouslystores the resonant frequency of when ink inside the container 194 isfull, that is, when ink is filled in the container 194 sufficiently, orwhen ink in the container 194 is end, that is, ink in the container 194is consumed, as one of the characteristic parameter. The resonantfrequency when the ink inside the container 194 is full status or endstatus can be stored when the ink container is mounted on the ink jetrecording apparatus for the first time. Moreover, the resonant frequencywhen the ink inside the container 194 is full status or end status canbe stored during the manufacturing of the container 194. Because theunevenness of the detection of the residual quantity of ink can becompensated by storing the resonant frequency when the ink inside thecontainer 194 is full status or end status in the semiconductor memorydevice 7 previously and reading out the data of the resonant frequencyat the ink jet recording apparatus side, it can be accurately detectedthat the residual quantity of ink is decreased to the reference value.

[0347]FIG. 47 shows further other embodiment of the ink cartridge 180.The ink cartridge 180E shown in FIG. 47(A) mounts a actuator 606 whichis long in vertical direction on the side wall 194 b of the container194. The wave preventing wall 1192 x is provided inside the container194 such that the wave preventing wall 1192 x faces to the whole of thevibrating region of the actuator 106. The change of the residualquantity of ink inside the container 194 can be detected continuously bythe actuator 606 which is long in vertical direction. The length of theactuator 606 is preferably longer than the half of the height of theside wall 194 b. In FIG. 47(A), the actuator 606 has the length from thesubstantially from the top end to the bottom end of the side wall 194 b.Therefore, the wave preventing wall 1192 x also has a lengthsubstantially from the top end to the bottom end of the side wall 194 b.By providing the wave preventing wall 1192 x, the wave preventing wall1192 x prevents the wave of ink around the actuator 606 and prevents themalefaction of the actuator 606. Furthermore, the wave preventing wall1192 x prevents the bubble generated by the waving of ink to enter tothe actuator 606.

[0348] The ink cartridge 180F shown in FIG. 47(B) mounts a plurality ofactuators 106 on the side wall 194 b of the container 194 and comprisesa wave preventing wall 1192 x on the face of the plurality of actuators606. The ink cartridge 180F further comprises the wave preventing wall1192 x, which is long in vertical direction, along the side wall 194 bwith predetermined gap with the side wall 194 b inside the container194. A gap which is filled with ink is formed between the actuator 106and the wave preventing wall 1192 x. Moreover, the gap between the wavepreventing wall 1192 x and the actuator 106 has a enough distance suchthat the gap does not hold ink by capillary force. When the container194 is rolled, ink wave is generated inside the container 194 by thewaving, and there is possibility that the actuator 106 malfunctions bydetecting gas or an air bubble caused by the shock of the ink wave. Assimilar to the embodiment shown in FIG. 47(B), by providing the wavepreventing wall 1192 x, ink wave around the actuator 106 can beprevented so that the malfunction of the actuator 106 can be prevented.The wave preventing wall 1192 x also prevents the air bubble generatedby the waving of ink to enter to the actuator 106.

[0349]FIG. 48 shows further other embodiment of the ink cartridge 180.The ink cartridge 180G shown in FIG. 48(A) has a top wall 1080 and abottom wall 1090, each of which is located on the upside and downside ofthe ink surface inside the container 194. A plurality of wave preventingwalls 212 a are extended from the top wall 1080 downward to the bottomwall 1090. Because each of lower end of the partition walls 212 and thebottom face of the container 194 has a predetermined gap, the bottompart of the container 194 communicates with each other. The inkcartridge 180G has a plurality of containing chambers 213 divided by theeach of plurality of partition walls 212. The bottom part of theplurality of the containing chambers 213 communicates with each other.The actuator 106 is mounted on the side wall 1070 which faces to the inksupply port 187. The actuator 106 is arranged on substantially center ofthe top face 194 c of the containing chamber 213 of the container 194.The volume of the containing chamber 213 is arranged such that thevolume of the containing chamber 213 of the ink supply port 187 is thelargest, and the volume of the containing chamber 213 graduallydecreases as the distance from the ink supply port 187 increases to theinner part of the ink cartridge 180G. Therefore, the containing chamber213 becomes wider towards from the actuator 106 mounting side of thecontaining chamber 213 to the ink supply port 187 side of the containingchamber 213.

[0350] Because ink is drained from the ink supply port 187, and airenters from the air introducing inlet 185, ink is consumed from thecontaining chamber 213 of the ink supply port 187 side to the containingchamber 213 of the inner part of the ink cartridge 180G. For example,the ink in the containing chamber 213 which is most near to the inksupply port 187 is consumed, and during the ink level of the containingchamber 213 which is most near to the ink supply port 187 decreases, theother containing chamber 213 are filled with ink. When the ink in thecontaining chamber 213 which is most near to the ink supply port 187 isconsumed totally, air enters to the containing chamber 213 which issecond by counted from the ink supply port 187, then the ink in thesecond containing chamber 213 is beginning to be consumed so that theink level of the second containing chamber 213 begin to decrease. Atthis time, ink is filled in the containing chamber 213 which is third ormore than third by counted from the ink supply port 187. In this way,ink is consumed from the containing chamber 213 which is most near tothe ink supply port 187 to the containing chamber 213 which is far fromthe ink supply port 187 in order.

[0351] As shown above, because the actuator 106 is arranged on thecontaining chamber 213 that is farthermost from the ink supply port 187,the actuator 106 can detect the ink end. Furthermore, the plurality ofwave preventing walls 212 acan effectively prevent the waves of ink.

[0352] The ink cartridge 180H shown in FIG. 48(B) has a top wall 1080and a bottom wall 1090, each of which is located on the upside anddownside of the ink surface inside the container 194. A plurality ofwave preventing walls 212 b are extended from the top wall 1080 and thebottom wall 1090 alternately. There are gap between the partition wall212 b, which extends from the bottom wall 1090, among the plurality ofthe wave preventing wall 212 b and the side wall, not shown in thefigure, located on width direction of the container 194. Therefore, thelevel of ink surface in each containing chamber 213 is equal.

[0353] Furthermore, among the plurality of wave preventing wall 212 b,the wave preventing wall 212 b which extends from the top wall 1090 andthe side wall, not shown in the figure, located on width direction ofthe container 194 can be coupled liquid-tightly or air-tightly. In casethe wave preventing wall 212 b which is nearest to the actuator 106among the plurality of wave preventing wall 212 b extends from the topwall 1080, gas enters to the containing chamber 213 which is nearest tothe actuator 106 when the level of ink surface inside the container 194reaches to the lower end of the wave preventing wall 212 b which isnearest to the actuator 106. Therefore, the level of ink surface fordetecting the ink end is determined by the position of the lower end 212f to the level of ink surface along a vertical direction

[0354] In the ink cartridge 180I shown in FIG. 48(C), the actuator 106is mounted on the side wall 1070 around the boundary of the side wall1070 and the top wall 1080. The ink cartridge 180I includes at least twocontaining chambers of containing chamber 213 a and containing chamber213 b which are partitioned by the wave preventing wall 212 c. Among twocontaining chambers, a negative pressure generating member 1100 whichgenerates a negative pressure is provided on the supply port sidecontaining chamber 213 a which is relatively near to the ink supply port187. Among two containing chambers, the actuator 106 is provided on theinner side containing chamber 213 b which is relatively far from the inksupply port 187.

[0355] A buffer 214 is formed on the top wall 1080 of the containingchamber 213 b. The buffer 214 is a concave part which accepts the bubblewhich enters into the ink cartridge 180I when the ink cartridge 180I ismanufactured or when the ink cartridge 180I is left for a long periodwithout to be used. In FIG. 48(C), the buffer 214 is formed as a concavepart which overhangs from the side wall 194 b of the container 194.Because the negative pressure generating member 1100 and the buffer 214accepts the bubbles enters inside the containing chamber 213 b, thenegative pressure generating member 1100 and the buffer 214 can preventthe malfunction of the actuator 106 such as detecting the ink end by theattaching of bubbles on the actuator 106. Furthermore, the ink quantitywhich can be consumed after detecting the ink end can be changed bychanging the capacity of containing chamber 213 b and the length of thewave preventing wall 212 c.

[0356] In the ink cartridge 180J shown in FIG. 48(D), a plurality ofwave preventing walls 212 d are extended from the side wall 1070 and theside wall 1110 of the container 194 alternately. Furthermore, each ofone end 212 dd of each of the wave preventing wall 212 d is slopedtoward the upside of ink surface. Moreover, A gap, in a degree which canpass through ink, is provided between the each of wave preventing walls212 d and the side wall, not shown in the figure, which intervenebetween the side wall 1070 of the container 194 and the side wall 1110.Therefore, ink does not remain on the wave preventing wall 212 d. Aplurality of actuators 106 are mounted on the side wall 1070 whichextends substantially vertically to ink surface among the wall ofcontainer 194. A plurality of actuators 106 is mounted on the differentheight to the ink surface with each other. Thereby the actuator 106 candetect the ink consumption status step by step. In the presentembodiment, the buffer 214 is provided around the side wall 1070 of theactuator 106 mounting side among the top wall 1080.

[0357]FIG. 49 shows a plan cross sectional view of the further anotherembodiment of the ink cartridge according to the present invention. Inthe ink cartridge 180K of the present embodiment, the actuator 106 ismounted on the side wall 1070 which faces to the ink supply port 187.Each of a plurality of wave preventing wall 212 e extends from the firstside wall 1120 a and the second side wall 1120 b, which intervenebetween side wall 1070 and the side face where the ink supply port 187is provided, alternatively. By the plurality of wave preventing wall 212e which extends from the side wall 1120 a and the 1120 b, the actuator106 is effectively protected from the wave of ink and the generation ofthe bubbles is suppressed.

[0358]FIG. 50 shows a plan cross sectional view of the further anotherembodiment of the ink cartridge according to the present invention. Inthe ink cartridge 180L of the present embodiment, the actuator 106 ismounted on the side wall 1070 which faces to the ink supply port 187.The wave preventing wall 212 g includes a bending part 800, at least apart of the end of the wave preventing wall of which is bent toward theside wall 1070 where the actuator 106 is mounted. A capillary force doesnot work between the wave preventing wall 212 g and the actuator 106.Furthermore, a gap, on which a capillary force works, is providedbetween the bending part 800 and the side wall 1070. Therefore, theentering of the bubbles between the actuator 106 and the wave preventingwall 212 g can be prevented. The ink level around the actuator 106 isequal to the other ink level in the ink cartridge 180L. Therefore, theactuator 106 can accurately detect the ink consumption status inside theink cartridge 180L.

[0359]FIG. 51 shows other embodiment of the ink cartridge using theactuator 106. The ink cartridge 220A shown in FIG. 51(A) has a firstwave preventing wall 222 provided such that it extends from the top wall1081, which locates upside of the ink surface, downward to the inksurface among the wall of the ink cartridge 220A. Because there is apredetermined gap between the lower end of the first wave preventingwall 222 and the bottom wall 1091 of the ink cartridge 220A, ink canflows into the ink supply port 230 through the bottom face of the inkcartridge 220A. A second wave preventing wall 224 is formed such thatthe second wave preventing wall 224 extends upward from the bottom faceof the ink cartridge 220A on the ink supply port 230 side of the firstwave preventing wall 222. Because there is a predetermined gap betweenthe upper end of the second wave preventing wall 224 and the top face ofthe ink cartridge 220A, ink can flows into the ink supply port 230through the top face of the ink cartridge 220A.

[0360] A ventilation side ink chamber 225 a is formed on the inner partof the first wave preventing wall 222, seen from the ink supply port230, by the first wave preventing wall 222. On the other hand, adetection side ink chamber 225 b is formed on the front side of thesecond wave preventing wall 224, seen from the ink supply port 230, bythe second wave preventing wall 224. The volume of the ventilation sideink chamber 225 a is larger than the volume of the detection side inkchamber 225 b. A detection side small ink chamber 227 is formed byproviding a gap, which can generate the capillary phenomenon, betweenthe first wave preventing wall 222 and the second wave preventing wall224. Therefore, the ink in the ventilation side ink chamber 225 a iscollected to the detection side small ink chamber 227 by the capillaryforce of the detection side small ink chamber 227. Therefore, thedetection side small ink chamber 227 can prevent that the air or airbubble enters into the detection side ink chamber 225 b. Furthermore,the ink level in the detection side ink chamber 225 b can decreasesteadily and gradually. Because the ventilation side ink chamber 225 ais formed at more inner part of the detection side ink chamber 225 b,seen from the ink supply port 230, the ink in the detection side inkchamber 225 b is consumed after the ink in the ventilation side inkchamber 225 a is consumed.

[0361] The actuator 106 is mounted on the side wall 1071 of the inkcartridge 220A of the ink supply port 230 side, that is, the side wall1071 of the detection side ink chamber 225 b of the ink supply port 230side. The actuator 106 detects the ink consumption status inside thedetection side ink chamber 225 b. The residual quantity of ink at thetiming closed to the ink near end can be detected stably by mounting theactuator 106 on the side wall 1071 of the detection side ink chamber 225b. Furthermore, by changing the height of the mounting position of theactuator 106 on the side wall 1071 of the detection side ink chamber 225b, the timing to determine which ink residual quantity as an ink end canbe freely set. Because ink is sullied from the ventilation side inkchamber 225 a to the detection side ink chamber 225 b by the detectionside small ink chamber 227, the actuator 106 does not influenced by thewaving of ink caused by the waving of the ink cartridge 220A, andactuator 106 can thus reliably measure the ink residual quantity.Furthermore, because the detection side small ink chamber 227 holds ink,the detection side small ink chamber 227 can prevent ink to flowbackward from the detection side ink chamber 225 b to the ventilationside ink chamber 225 a.

[0362] A check valve 228 is provided on the top face of the inkcartridge 220A. The leaking of ink outside of the ink cartridge 220Acaused by the waving of the ink cartridge 220A can be prevented by thecheck valve 228. Furthermore, the evaporation of ink from the inkcartridge 220A can be prevented by providing the check valve 228 on thetop face of the ink cartridge 220A. If ink in the ink cartridge 220A isconsumed, and negative pressure inside the ink cartridge 220A exceedsthe pressure of the check valve 228, the check valve 228 opens andintroduces air into the ink cartridge 220A. Then the check valve 228closes to maintain the pressure inside the ink cartridge 220A to bestable.

[0363]FIG. 51(C) and (D) shows a detailed cross-section of the checkvalve 228. The check valve 228 shown in FIG. 51(C) has a valve 232 whichincludes flange 232 a formed by rubber. An airhole 233, whichcommunicates air between inside and outside of the ink cartridge 220, isprovided on the ink cartridge 220 such that the airhole 233 faces to theflange 232 a. The airhole 233 is opened and closed by the flange 232 a.The check valve 228 opens the flange 232 a inward the ink cartridge 220when the negative pressure in the ink cartridge 220 exceeds the pressureof the check valve 228 by the decrease of ink inside the ink cartridge220A, and thus the air outside the ink cartridge 220 is introduced intothe ink cartridge 220. The check valve 228 shown in FIG. 51(D) has avalve 232 formed by rubber and a spring 235. If the negative pressureinside the ink cartridge 220 exceeds the pressure of the check valve228, the valve 232 presses and opens the spring 235 to introduce theoutside air into the ink cartridge 220 and then closes to maintain thenegative pressure inside the ink cartridge 220 to be stable.

[0364] The ink cartridge 220B shown in FIG. 51(B) has a porous member242 in the ventilation side ink chamber 225 a instead of providing thecheck valve 228 on the ink cartridge 220A as shown in FIG. 51(A). Theporous member 242 holds the ink inside the ink cartridge 220B and alsoprevents ink to be leaked outside of the ink cartridge 220B during thewaving of the ink cartridge 220B.

[0365]FIG. 52 is a cross sectional view of an embodiment of an inkcartridge for use with a single color, for example, the black ink as anembodiment of the liquid container according to the present invention.An ink cartridge shown in FIG. 52 is based on the method that detectsthe position of the liquid surface or an existence of liquid inside aliquid container by detecting a resonant frequency by measuring thecounter electromotive force generated by the residual vibration remainedin the vibrating section among the above mentioned method. The actuator106 is used for an embodiment of the liquid censor that detects liquid.The ink cartridge of the embodiment shown in FIG. 52 comprises acontainer 1 which contains liquid K and includes top wall 1030 locatedupside of the liquid surface of ink K, an ink supply port 2 whichsupplies liquid K outside the container 1, an actuator 106 which detectsink consumption status inside the container 1, and a first partitionwall 193 a which partitions at least two ink chamber such that ink K inboth of the ink chamber can communicate with each other inside thecontainer 1. At least two ink chambers include a ventilation side inkchamber 123 a which communicate with atmosphere and the detecting sideink chamber 123 b. The actuator 106 is mounted on the top wall 1030 ofthe ink chamber 123 b.

[0366] The airhole 233 is provided on the top wall 1030 of theventilation side ink chamber 123 a which ventilates with atmosphere. Thecheck valve 228 shown in FIG. 56 can be used for airhole 233. However,the form of the airhole 233 is not limited to the check valve 228 shownin FIG. 56. If ink K is consumed and the container 1 inside becomesextremely negative pressure, air is introduced to the ventilation sideink chamber 123 a from the outside of the container 1 by the airhole233, and the airhole 233 thus prevents the pressure inside the container1 to be negative. Therefore, with the consumption of ink advanced, airis introduced to the ventilation side ink chamber 123 a through theairhole 233, and the level of liquid surface of ink K decreases.

[0367] The partition wall 193 a is coupled with the top wall 1030liquid-tightly. Therefore, even the ink is consumed, ink K is filled inthe detection side ink chamber 123 b in the container 1 until the levelof liquid surface of ink K reaches to the lower end 193 aa of thepartition wall 193 a. When the ink consumption advances and the level ofliquid surface of ink K reaches to the lower end 193 aa of the partitionwall 193 a, gas enters to the detection side ink chamber 123 b. Therebythe ink k remained in the detection side ink chamber 123 b flows out tothe ink supply port 2, and the medium existed around the actuator 106changes from ink K to atmosphere. Therefore, the actuator 106 can detectthat the status inside the ink cartridge is in ink end status. Thus, itis the lower end 193 aa to determine which level of the liquid surfaceof ink K to be a ink end. Furthermore, the volume of the detection sideink chamber 132 b is determined by the width between the side wall 1010,which extends substantially vertical to the ink surface, and thepartition wall 193 a. Therefore, the ink quantity remains inside thecontainer 1 when detecting the ink end can be set by the width betweenthe side wall 1010 and the partition wall 193 a and the height of thelower end 193 aa in the direction vertical to the ink surface.

[0368] The volume of the detection side ink chamber 123 b is preferablyhalf or smaller than half of the volume of the ventilation side inkchamber 123 a. A capillary force such as to hold ink K does not work onthe detection side ink chamber 123 b.

[0369] The actuator 106 can be used as a means of merely detecting thevibration without vibrating itself. Moreover, the detailed configurationof the airhole will be described in FIG. 56.

[0370] A packing ring 4 and a valve body 6 are provided in the inksupply port 2. Referring to FIG. 54, the packing ring 4 is engaged withthe ink supply needle 32 communicating with a recording head 31, in afluid-tight manner. The valve body 6 is constantly and elasticallycontacted against the packing ring 4 by way of a spring 5. When the inksupply needle 32 is inserted, the valve body 6 is pressed by the inksupply needle 32 so as to open an ink passage, so that ink inside thecontainer 1 is supplied to the recording head 31 via the ink supply port2 and the ink supply needle 32. On an upper wall of the container 1,there is mounted a semiconductor memory means 7 which stores data on inkinside the ink cartridge.

[0371] If there is no partition wall 193 a in the container 1, bubblesmay be generated by the waving of ink, which is caused by the vibrationof ink cartridge generated by such as the scanning operation during theprinting process. Then, there is a danger that the actuator 106 maydetect mistakenly that there is enough ink in the container 1 if the inkattaches to the actuator 106 by the waving of ink even if there islittle amount of ink in the container 1. Moreover, there is also adanger that the actuator 106 may detect mistakenly that there is no inkif the bubble attaches to the actuator 106 even if the ink is filled inthe container 1.

[0372] However, according to the embodiment of the liquid container ofthe present embodiment, the partition wall prevents the waving of inkaround the piezoelectric device even when the ink cartridge vibrates bysuch as the scanning operation during the printing process. Bypreventing the waving of ink around the piezoelectric device, thepartition wall 193 a prevents the generation of the bubbles.Furthermore, even the bubbles generate in the ventilation side inkchamber, the partition wall separates the ventilation side ink chamberand the detection side ink chamber air-tightly and liquid-tightly.Therefore, the partition wall prevents the bubbles to move close to theactuator 106 and contact with the actuator 106.

[0373] There is no limitation of the size, thickness, shape,flexibility, and material for the partition wall. Therefore, the size ofthe partition wall can be made relatively larger or smaller. Thethickness of the partition wall can be made relatively thicker orthinner. Furthermore, the shape of the partition wall can be square orrectangular. Preferably the shape, size and thickness of the partitionwall is changed according to the shape of the ink cartridge.Furthermore, the partition wall can be made from the hard material orflexible material. For example, material such as plastic, tefron, nylon,polypropylene, or PET can be used for the partition wall. Preferably,the partition wall is made from the air-tight or liquid-tight materialwhich does not pass through gas or liquid. Moreover, the container andthe partition wall are made from same material so that the container andthe partition wall can be formed in one body. The manufacturing processof the ink cartridge can thereby be reduced.

[0374]FIG. 53 is a perspective view of the ink cartridge which storesplural types of inks, viewed from an outside thereof, according to anembodiment. FIG. 53 is a perspective view from the side of the top wall1038 which is located upside of the liquid surface of ink K among thewall of the container 8. A container 8 is divided into three inkchambers 9, 10 and 11. Ink supply ports 12, 13 and 14 are formed for therespective ink chambers. On a top wall 1038 of the respective inkchambers 9, 10 and 11, the respective actuators 15, 16 and 17 aremounted on the container 8 so that the actuators 15, 16, and 17 cancontact with the ink which is housed in each ink chambers via thethrough hole, not shown in the figure, provided on the container 8.Partition walls, not shown in the figure, is provided each of inside ofthe ink container 9, 10 and 11 as similar to the ink cartridge shown inFIG. 52. The partition walls provided in each of ink chambers 9, 10, and11 separates the each ink chambers 9, 10, and 11 into ventilation sideink chamber and detection side ink chamber.

[0375]FIG. 54 is a cross sectional view showing an embodiment of a majorpart of the ink-jet recording apparatus suitable for the ink cartridgeshown in FIGS. 52 and 53. A carriage 30 capable of reciprocating in thedirection of the width of the recording paper is equipped with a subtankunit 33, while the recording head 31 is provided in a lower face of thesubtank unit 33. Moreover, the ink supply needle 32 is provided in anink cartridge mounting face side of the subtank unit 33. In FIG. 54, theink cartridge shown in FIGS. 52 and 53 are used. However, the inkcartridge shown in other figures also can be used.

[0376] When the ink supply port 2 of the container 1 is inserted throughthe ink supply needle 32 of the subtank unit 33, the valve body 6recedes against the spring 5, so that an ink passage is formed and theink inside the container 1 flows into the ink chamber 34. At a stagewhere the ink chamber 34 is filled with ink, a negative pressure isapplied to a nozzle opening of the recording head 31 so as to fill therecording head with ink. Thereafter, the recording operation isperformed.

[0377] When the ink is consumed in the recording head 31 by therecording operation, a pressure in the downstream of the flexible valve36 decreases. Then, the flexible valve 36 is positioned away from avalve body 38 so as to become opened. When the flexible valve 36 isopened, the ink in the ink chamber 34 flows into the recording head 31through the ink passage 35. Accompanied by the ink which has flowed intothe recording head 31, the ink in the container 1 flows into the subtankunit 33 via the ink supply needle 32.

[0378]FIG. 55 is a cross sectional view of an another embodiment of anink cartridge as an embodiment of the liquid container according to thepresent invention. In an ink cartridge of the present embodiment, a topwall 1039, which locates upside of the liquid surface of ink K, issloped to the liquid surface of ink K. The actuators 106 are mounted onthe top wall 1039 such that the actuator 106 can contacts with inkthrough the through hole 1 c provided on the top wall 1039. Thepartition wall 193 c extends from the top wall 1039 downward to the inksurface. Furthermore, the present embodiment has a second partition wall193 d which extends from the top wall 10398 inside the detection sideink chamber 123 b and separates the detection side ink chamber 123 b atleast into two detection side small ink chambers 1123 a and 1123 b suchthat ink housed in both of the detection side small ink chamber 1123 aand 1123 b can communicate each other. Each of two actuators 106 a and106 b is mounted on the top wall 1039 of each of the detection sidesmall ink chambers 1123 a and 1123 b, respectively.

[0379] The volume of the ventilation side ink chamber 123 a which isclose to the ink supply port 2 is larger than the volume of thedetection side ink chamber 123 b which is relatively far from the inksupply port 2. Furthermore, the volume of the detection side small inkchamber 1123 a which is close to the ink supply port 2 is larger thanthe volume of the detection side small ink chamber 1123 b which isrelatively far from the ink supply port 2 within the detection side inkchamber 123 b. Therefore, ink in the ventilation side ink chamber 123 ais consumed at first. With consumption of ink advanced, the level of inksurface in the ventilation side ink chamber 123 a decreases. On theother hand, because the partition wall 193 cc and the top wall 1039 iscoupled liquid-tightly or air-tightly, the detection side ink chamber123 b is filled with ink until the level of ink surface reaches to thelower end 193 cc of the partition wall 193 c.

[0380] Next, if the ink surface in the ventilation side ink chamber 123a reaches to the lower end 193 cc of the partition wall 193 c, ink inthe detection side small ink chamber 1123 a is beginning to be consumedbecause ink in the detection side small ink chamber 1123 a flows out tothe ink supply port 2. With consumption of ink advanced, the level ofink surface in the detection side small ink chamber 1123 a decreases. Onthe other hand, because the partition wall 193 dd and the top wall 1039is coupled liquid-tightly or air-tightly, the detection side small inkchamber 1123 b is filled with ink until the level of ink surface reachesto the lower end 193 dd of the partition wall 193 d. Finally, if thelevel of ink surface of the detection side small ink chamber 1123 areaches to the lower end 193 dd of the partition wall 193 d, ink in thedetection side small ink chamber 1123 b is beginning to be consumedbecause ink in the detection side small ink chamber 1123 b flows out tothe ink supply port 2.

[0381] Therefore, the actuators 106 a and 106 b can detect the inkconsumption status step by step. Moreover, because the volume of the inkchambers are designed such that the volume decreases from theventilation side ink chamber 123 a, which is nearest to the ink supplyport 2, to the detection side small ink chamber 1123 a and further tothe detection side small ink chamber 1123 b, which is farthest from theink supply port 2, the frequency of detecting an ink by the actuators106 a and 106 b increases with the advance of ink consumption.Therefore, the frequency of detection of ink increases with thedecreasing of residual quantity of ink.

[0382] The container of the ink cartridge shown in FIG. 55 has onesecond partition wall. As other embodiment, the container can have aplurality of partition walls so that the detection side ink chamber 123b is separated into three or over detection side small ink chambers. Aplurality of second partition walls separates the detection side inkchamber 123 b into two or over detection side small ink chambers. Eachof the volumes of the of the detection side small ink chambers 1123 bcan be varied gradually from the one side of the side wall to the otherside of side wall which faces each other. Preferably, as shown in FIG.55, each of the volume of the detection side small ink chambersdecreases gradually from the detection side small ink chamber, which isrelatively near to the ink supply port 2, to the detection side smallink chamber, which is relatively far from the ink supply port 2. Then,the actuator 106 can detects the process of gradual consumption of ink Kinside the ink cartridge.

[0383] Moreover, because the volume of the ink chambers are designedsuch that the volume decreases from the detection side small ink chamber1123 a, which is near to the ink supply port 2, to the detection sidesmall ink chamber, which is far from the ink supply port 2, the timeinterval of detecting a decrease of ink by the actuator 106 graduallydecreases as the ink cartridge shown in FIG. 55. Therefore, thefrequency of detection of ink increases with the decreasing of residualquantity of ink.

[0384] Furthermore, the actuator 106 a is mounted nearby the partitionwall 193 c, and the actuator 106 b is mounted nearby the partition wall193 d. Therefore, even if the bubble G generates and enters into thedetection side ink chamber 123 b when the ink inside the ventilationside ink chamber 123 a does not reach to the lower end 193 cc of thepartition wall 193 c, the bubble G stays in the upper side of boundarybetween the top wall 1039 and the partition wall 193 c or the upper sideof boundary between the top wall 1039 and the side wall 1030. Therefore,the bubble G does not attaches to the actuator 106.

[0385]FIG. 56 shows further other embodiment of the ink cartridge usingthe actuator 106. The ink cartridge 220A shown in FIG. 56(A) has a firstpartition wall 222 provided such that it extends downward from the topface of the ink cartridge 220A. Because there is a predetermined spacebetween the lower end of the first partition wall 222 and the bottomface of the ink cartridge 220A, ink can flows into the ink supply port230 through the bottom face of the ink cartridge 220A. A secondpartition wall 224 is formed such that the second partition wall 224extends upward from the bottom face of the ink cartridge 220A on themore ink supply port 230 side of the first partition wall 222. Becausethere is a predetermined space between the upper end of the secondpartition wall 224 and the top face of the ink cartridge 220A, ink canflows into the ink supply port 230 through the top face of the inkcartridge 220A.

[0386] A ventilation side ink chamber 225 a is formed relatively near tothe airhole 233. On the other hand, a detection side ink chamber 225 bis formed relatively far from the airhole 233. By the second partitionwall 224, the detection side ink chamber 225 b and a detection sidesmall ink chamber 227 are formed. The volume of the ventilation side inkchamber 225 a is larger than the volume of the detection side inkchamber 225 b. A detection side small ink chamber 227 is formed byproviding a gap, which can generate the capillary phenomenon, betweenthe first partition wall 222 and the second partition wall 224.Therefore, the ink in the ventilation side ink chamber 225 a iscollected to the detection side small ink chamber 227 by the capillaryforce of the detection side small ink chamber 227. The first partitionwall 222 can prevent that the gas or air bubble to enter into thedetection side ink chamber 225 b. Furthermore, the ink level in thedetection side ink chamber 225 b can decrease steadily and gradually.Because the ventilation side ink chamber 225 a is formed at more innerpart of the detection side ink chamber 225 b, seen from the ink supplyport 230, the ink in the detection side ink chamber 225 b is consumedafter the ink in the ventilation side ink chamber 225 a is consumed.

[0387] Because ink is supplied from the ventilation side ink chamber 225a to the detection side ink chamber 225 b by the detection side smallink chamber 227, the actuator 106 does not influenced by the rolling ofink caused by the rolling of the ink cartridge 220A, and actuator 106can thus reliably measure the ink residual quantity. Furthermore,because the detection side small ink chamber 227 holds ink, thedetection side small ink chamber 227 can prevent ink to flow backwardfrom the detection side ink chamber 225 b to the ventilation side inkchamber 225 a.

[0388] The actuator 106 is mounted on the top wall 1013 of the inksupply port 230 side of the detection side ink chamber 225 b. Theactuator 106 detects the ink consumption status inside the detectionside ink chamber 225 b. The residual quantity of ink at the timingclosed to the ink near end can be detected stably by mounting theactuator 106 on the side wall of the detection side ink chamber 225 b.

[0389] A airhole 233 is provided on the top wall 1013 of the inkcartridge 220A. Moreover, a check valve 228 is provided on the airhole233. The leaking of ink outside the ink cartridge 220A caused by therolling of the ink cartridge 220A can be prevented by the check valve228. Furthermore, the evaporation of ink from the airhole 233 of the inkcartridge 220A can be prevented by providing the check valve 228 on thetop face of the ink cartridge 220A. If ink in the ink cartridge 220A isconsumed, and negative pressure inside the ink cartridge 220A exceedsthe pressure of the check valve 228, the check valve 228 opens andintroduces air into the ink cartridge 220A. Then the check valve 228closes to accelerate the drainage of ink from the ink cartridge 220A.

[0390]FIG. 57 shows further another embodiment of the ink cartridgeusing the actuator 106. An ink cartridge 180A shown in FIG. 57 has apartition wall 212 a which extends downward from the top face 194 c ofthe ink container 194. The container 194 is separated into a ventilationside ink chamber 213 a and a detection side ink chamber 213 b by thepartition wall 212 a. Because lower end 212 aa of the partition wall 212a and the bottom wall 1 a of the container 194 have a predeterminedspace, the ventilation side ink chamber 213 a and the detection side inkchamber 213 b communicates with each other. The actuator 106 is mountedon the top wall 194 c of the detection side ink chamber 213 b. Thevolume of the detection side ink chamber 213 b is smaller than thevolume of the ventilation side ink chamber 213 a. The volume of thedetection side ink chamber 213 b is preferably smaller than the half ofthe volume of the ventilation side ink chamber 213 a.

[0391] A buffer 214 a, that is a concave part for accepting the airbubble which enters to the ink cartridge 180A is formed on the top wall194 c of the detection side ink chamber 213 b. In FIG. 57, the buffer214 a is formed as a concave part overhang upward from the top wall 194c of the container 194. The buffer 214 a accepts the air bubble whichenters into the detection side ink chamber 213 b mistakenly when the inkis filled in the detection side ink chamber 213 b. The buffer 214 athereby prevents the bubbles to attach to the actuator 106. Therefore,the buffer 214 b prevents the malfunction of the actuator 106 to detectthe ink end wrongly by the attaching of air bubble to the actuator 106.Furthermore, by adjusting the volume of the detection side ink chamber213 b by changing the length of the partition wall 212 a or changing thewidth between the partition wall 212 a and the side wall 194 b, thepredetermined ink quantity remained after the detection of the ink endcan be changed.

[0392]FIG. 58 shows further another embodiment of the ink cartridge 180.An ink cartridge 180B shown in FIG. 58 has a partition wall 212 b whichis formed in L-shape. The partition wall 212 f extends from a top wall194 c. A lower end 212bb of the partition wall 212 b is longer than thelower end 212 aa of the partition wall 212 a in the embodiment shown inFIG. 57. Therefore, gas existed in the ventilation side ink chamber 213a is difficult to enter into the detection side ink chamber 213 b.Therefore, the malfunction of the actuator 106 to detects the ink endwrongly caused by the attaching of bubble to the actuator 106 can befurther prevented. Furthermore, a gap is provided between the lower end212 bb and the bottom wall 1 a. A capillary force, which can hold ink,does not work on the gap provided between the lower end 212 bb and thebottom wall 1 a.

[0393]FIG. 59 shows further another embodiment of the ink cartridge 180.An ink cartridge 180C shown in FIG. 59 has a partition wall 212 c whichis sloped toward the ink surface. The partition wall 212 c extends froma top wall 194 c. The distance between the side wall 194 b of the inkcartridge 180C and the partition wall 212 c narrows toward downside.Therefore, gas existed in the ventilation side ink chamber 213 a isdifficult to enter into the detection side ink chamber 213 b. Therefore,the malfunction caused by the attaching of bubble to the actuator 106can be further prevented. Furthermore, a gap is provided between thelower end 212 cc and the bottom wall 1 a of the container 194. Acapillary force, which can hold ink, does not work on the gap providedbetween the lower end 212 cc of the partition wall 212 c and the sidewall 194 b.

[0394]FIG. 60 shows further another embodiment of the ink cartridge 180.An ink cartridge 180D shown in FIG. 60 has a first partition wall 212 dwhich extends downward from the top face 194 c of the ink container 194.Furthermore, a second wall extends from the first partition wall 212 dtoward the side wall 194 b substantially parallel to the ink surface.The container 194 is separated into a ventilation side ink chamber 213 aand a detection side ink chamber 213 b by the first partition wall 212d. Furthermore, the second partition wall 212 e separates the detectionside ink chamber into a first detection side ink chamber 213 c and asecond detection side ink chamber 213 d. A gap is provided between thebottom wall 1 a and the first partition wall 212 d. Furthermore, a gapis provided between the side wall 194 b and the one end 212 ee of thesecond partition wall 212 e. A concave part is provided on a part of topwall 194 c to form a buffer 214 a which accepts the bubble.

[0395] One end of the second partition wall 212 e, which extends fromthe partition wall 212 d toward the side wall 194 b, extends until tothe position where just under the buffer 214 b. Therefore, first, thefirst partition wall 212 d prevents the entering of bubble into thefirst detection side ink chamber 213 c. If the bubble enters into thedetection side ink chamber 213 c mistakenly, the bubble is introduced tothe position which is just under the buffer 214 a by the secondpartition wall 212 e. Therefore, the bubble is caught by the buffer 214a. Therefore, the malfunction of the actuator 106 to detects the ink endwrongly by the attaching of bubble to the actuator 106, which isprovided in the second detection side ink chamber 213 d, can be furtherprevented.

[0396]FIG. 61 shows further another embodiment of the ink cartridge 180.An ink cartridge 180E shown in FIG. 61 has a partition wall 212 a assame as the partition wall 212 a of FIG. 57. The partition wall 212 aextends downward from the top face 194 c of the ink container 194. Thecontainer 194 is separated into a ventilation side ink chamber 213 a anda detection side ink chamber 213 b by the partition wall 212 a. A gap isprovided between the bottom wall 1 a and the partition wall 212 a.Furthermore, a concave part is provided on a part of top wall 194 c toform a buffer 214 b which accepts the bubble. A tapered face 1040 isprovided between the buffer 214 b and the actuator 106.

[0397] Therefore, first, the partition wall 212 a prevents the enteringof bubble into the detection side ink chamber 213 b. If the bubbleenters into the detection side ink chamber 213 b mistakenly, the bubbleis directly caught by the buffer 214 a or introduced to the buffer 214 balong the tapered face 1040. Therefore, the malfunction of the actuator106 to detects the ink end wrongly by the attaching of bubble to theactuator 106 can be further prevented. The shape and size of the buffercan be other arbitrary shape and size.

[0398]FIG. 62 shows further another embodiment of the ink cartridge 180.An ink cartridge 180F shown in FIG. 62 has a protruding part 214 f,which protrudes inside the container 194, on a part of the top wall 194c. The actuator 106 is mounted on the bottom part of the protruding part214 f. A partition wall 212 f extends downward from the top face 194 c.A buffer 214 c is provided for each of the position between the actuator106 and the partition wall 212 f and between the actuator 106 and theside wall 194 b. Therefore, the periphery of the actuator 106 issurrounded by the buffer 214 c.

[0399]FIG. 63 shows further another embodiment of the ink cartridge 180.An ink cartridge 180G shown in FIG. 63 has a partition wall 212 extendsdownward from the top face 194 c. The container 194 is separated into aventilation side ink chamber 213 a and a detection side ink chamber 213b by the partition wall 212 g. Uneven part is provided on the top wall194 c, and two actuators 106 are mounted on the protruding part whichprotrudes inside the detection side ink chamber 213 b. The concave partof the top wall 194 c works as a buffer 214 c which accepts bubble.

[0400]FIG. 64 shows further other embodiment of the ink cartridge 180.The ink cartridge 180I shown in FIG. 64 has a plurality of partitionwalls 212 h, 212 i, 212 j, and 212 k, each of which extends downwardfrom the top face 194 c of the ink container 194. The partition wall 212h is first partition wall, and the partition walls 212 i, 212 j, and 212k are the second partition walls. Because each of lower ends 212 hh, 212ii, 212 jj, and 212 kk of each of the partition walls 212 h, 212 i, 212j, and 212 k and the bottom wall 1 a of the container 194 have apredetermined gap, the bottom part of the container 194 communicateswith each other. The ink cartridge 180I has a ventilation side inkchamber 213 a and a plurality of detection side small ink chambers 213h, 213 i, 213 j, and 213 k separated by the each of plurality ofpartition walls 212 h, 212 i, 212 j and 212 k. The bottom part of theventilation side ink chamber 213 a and a plurality of the detection sidesmall ink chambers 213 h, 213 i, 213 j, and 213 k communicates with eachother. Each of the actuators 106 h, 106 i, 106 j, and 106 k is mountedon the top face 194 c of each of the plurality of the detection sidesmall ink chambers 213 h, 213 i, 213 j, and 213 k, respectively. Each ofthe actuators 106 h, 106 i, 106 j, and 106 k is arranged onsubstantially center of the top face 194 c of each of the plurality ofthe detection side small ink chambers 213 h, 213 i, 213 j, and 213 k,respectively. The volume of the ink chamber is arranged such that thevolume of the ventilation side ink chamber 213 a which locates inksupply port 187 side is the largest. Moreover, the volume of the inkchamber gradually decreases as the distance from the ink supply port 187increases. Therefore, the volume of the detection side small ink chamber213 k which is farthest from the ink supply port 187 is the smallestamong the volume of the ink chambers.

[0401] Because gas is introduced from the airhole 233, ink is consumedfrom the ventilation side ink chamber 213 a of the ink supply port 187side to the detection side ink chamber 213 k. For example, the ink inthe ventilation side ink chamber 213 a which is nearest to the inksupply port 187 is consumed, and during the ink level of the ventilationside ink chamber 213 a decreases, the other detection side small inkchambers are filled with ink. When the ink level in the ventilation sideink chamber 213 a reaches to the lower end 212 hh of the partition wall212 h, air enters into the detection side small ink chamber 213 h, andthen the ink in the detection side small ink chamber 213 h is beginningto be consumed. At this time, ink is filled in the detection side smallink chamber 213 i, 213 j, and 213 k. Furthermore, if the ink level inthe detection side small ink chamber 213 h reaches to the lower end 212ii of the partition wall 212 i, air enters into the detection side smallink chamber 213 i, and then the ink in the detection side small inkchamber 213 i is beginning to be consumed. In this way, ink issequentially consumed from the ventilation side ink chamber 213 a to thedetection side small ink chamber 213 k.

[0402] Each of the actuators 106 h, 106 i, 106 j, and 106 k is mountedon the top wall 194 c of each of the detection side small ink chambers.Therefore, the actuators 106 h, 106 i, 106 j, and 106 k can detect thedecrease of the ink quantity step by step. Furthermore, the volume ofthe ink chambers decreases from the ventilation side ink chamber 213 a,which is near to the ink supply port 187, to the detection side smallink chamber 213 k gradually. Therefore, the time interval of detectingthe decrease of the ink quantity gradually decreases. Therefore, thefrequency of the ink quantity detection can be increased as the ink endis drawing near.

[0403]FIG. 65 shows further other embodiment of the ink cartridge 180.FIG. 65 shows a cross section of an ink cartridge 180J. Thesemiconductor memory device 7 and the actuator 106 are formed on thesame circuit board 610 in the ink cartridge 180J.

[0404] The semiconductor memory device 7 can be constituted by thesemiconductor memory which can be rewritten such as EEPROM. Because thesemiconductor memory device 7 and the actuator 106 are formed on thesame circuit board 610, the mounting process can be finished at one timeduring mounting the semiconductor memory device 7 and the actuator 106on the ink cartridge 180C. Moreover, the working process during themanufacturing of the ink cartridge 180C and the recycling of the inkcartridge 180C can be simplified. Furthermore, the manufacturing cost ofthe ink cartridge 180C can be reduced because the numbers of the partscan be reduced. Furthermore, a partition wall 212J extends from the topwall 194 c downward to the ink surface. The partition wall 212J preventsthe waving of ink or bubbling. The partition wall 212J thereby preventsthe malfunction of the actuator 106.

[0405] The actuator 106 detects the ink consumption status inside thecontainer 194. The semiconductor memory device 7 stores the informationof ink such as residual quantity of ink detected by the actuator 106.That is, the semiconductor memory device 7 stores the informationrelated to the characteristic parameter such as the characteristic ofink and the ink cartridge used for the actuator 106 when detecting theink consumption status. The semiconductor memory device 7 previouslystores the resonant frequency of when ink inside the container 194 isfull, that is, when ink is filled in the container 194 sufficiently, orwhen ink in the container 194 is end, that is, ink in the container 194is consumed, as one of the characteristic parameter. The resonantfrequency when the ink inside the container 194 is full status or endstatus can be stored when the ink container is mounted on the ink jetrecording apparatus for the first time. Moreover, the resonant frequencywhen the ink inside the container 194 is full status or end status canbe stored during the manufacturing of the container 194. Because theunevenness of the detection of the residual quantity of ink can becompensated by storing the resonant frequency when the ink inside thecontainer 194 is full status or end status in the semiconductor memorydevice 7 previously and reading out the data of the resonant frequencyat the ink jet recording apparatus side, it can be accurately detectedthat the residual quantity of ink is decreased to the reference value.

[0406]FIG. 66 shows further other embodiment of the ink cartridge 180.The ink cartridge 180K shown in FIG. 66 has a plurality of partitionwalls 212 m, 212 n, 212 p, and 212 q, each of which extends downwardfrom the top face 194 c of the ink container 194. The partition wall 212m is the first partition wall, and the partition walls 212 n, 212 p, and212 q are the second partition walls. Because each of lower ends 212 mm,212 nn, 212 pp, and 212 qq of the partition walls 212 m, 212 n, 212 p,and 212 q, respectively, and the bottom wall of the container 194 has apredetermined gap, the bottom part of the container 194 communicateswith each other. Moreover, the length of the partition walls 212 m, 212n, 212 p, and 212 q increases from the side near to the airhole 233 inorder. Therefore, each of the gap between the lower ends 212 mm, 212 nn,212 pp, and 212 qq and the bottom wall 1 a narrows in the order of 212m, 212 n, 212 p, and 212 q, sequentially.

[0407] Furthermore, the ink cartridge 180K has a ventilation side inkchamber 213 a and a plurality of detection side small ink chamber 213 m,213 n, 213 p, and 213 q separated by the each of plurality of partitionwalls 212 m, 212 n, 212 p and 212 q. The bottom part of the ventilationside ink chamber 213 a and a plurality of the detection side small inkchambers 213 m, 213 n, 213 p, and 213 q communicates with each other.Each of the actuators 106 m, 106 n, 106 p, and 106 q is mounted on thetop face 194 c of each of the plurality of the detection side small inkchambers 213 m, 213 n, 213 p, and 213 q, respectively. Each of theactuators 106 m, 106 n, 106 p, and 106 q is arranged on substantiallycenter of the top face 194 c of each of the plurality of the detectionside small ink chambers 213 m, 213 n, 213 p, and 213 q, respectively.

[0408] If ink is consumed, gas is introduced from the airhole 233.Therefore, ink is consumed from the ventilation side ink chamber 213 awhich is near to the airhole 233 to the detection side ink chamber 213q. For example, the ink in the ventilation side ink chamber 213 a whichis nearest to the airhole 233 is consumed, and during the ink level ofthe ventilation side ink chamber 213 a decreases, the other detectionside small ink chambers are filled with ink. When the ink level in theventilation side ink chamber 213 a reaches to the lower end 212 mm ofthe partition wall 212 m, air enters into the detection side small inkchamber 213 m, and then the ink in the detection side small ink chamber213 m is beginning to be consumed. At this time, ink is filled in thedetection side small ink chamber 213 n, 213 p, and 213 q. Furthermore,if the ink level in the detection side small ink chamber 213 m reachesto the lower end 212 nn of the partition wall 212 n, air enters into thedetection side small ink chamber 213 n, and then the ink in thedetection side small ink chamber 213 n is beginning to be consumed. Inthis way, ink is sequentially consumed from the ventilation side inkchamber 213 a to the detection side small ink chamber 213 q.

[0409] Because the gap between the each of the lower ends and the bottomwall 1 a narrows gradually in the order from the lower ends 212 mm, 212nn, 212 pp, and 212 qq, ink is consumed in the order from theventilation side ink chamber 213 a, detection side small ink chamber 212m, 212 n, 212 p, and 212 q, sequentially. Therefore, the gas isdifficult to enter mistakenly into the ink chambers in the same ordermentioned above. For example, even if gas enters into the detection sidesmall ink chamber 213 m and 213 n mistakenly, and the actuator 106detects the ink end mistakenly, the partition walls 212 p and 212 q,which is longer than the partition walls 212 m and 212 n, prevents thegas to enter into the detection side small ink chamber 213 p and 213 q.Therefore, the actuators 106 p and 106 q do not mistakenly detect theink end. Thus, in the present embodiment, the actuator 106 q detects theink end finally and most reliably.

[0410] Furthermore, because the partition walls 212 m, 212 n, 212 p, and212 q prevent the waving of ink, the partition walls 212 m, 212 n, 212p, and 212 q also prevent the generation of the bubble.

[0411] Moreover, the intervals between each of the partition walls 212m, 212 n, 212 p, and 212 q with each other can be equal, and theinterval between the partition wall 212 q and the side wall 194 b of thecontainer 1 can be equal. In this case, the capacity of each of thedetection side small ink chambers 213 m, 213 n, 213 p, and 213 q can beadjusted by adjusting the length of the partition walls 212 m, 212 n,212 p, and 212 q.

[0412]FIG. 67 shows an embodiment around a recording head of part of theink cartridge and an ink jet recording apparatus which uses the actuator106. In the present embodiment, the ink cartridge 180A shown in FIG. 57is used. However, the ink cartridge in any of the ink cartridge shown inFIG. 58 to FIG. 64 also can be used. Furthermore, the ink cartridge ofthe other form also can be used. A plurality of ink cartridges 180A ismounted on the ink jet recording apparatus which has a plurality of inkintroducing members 182 and a holder 184 each corresponding to the eachof ink cartridge 180, respectively. Each of the plurality of inkcartridges 180A contains different types of ink, for example, differentcolor of ink. The actuator 106, which detects at least acousticimpedance, is mounted on the each of top wall of the plurality of inkcartridge 180A. The actuator 106 and a partition wall 212 a are providedfor each top wall of the plurality of ink cartridge 180A. The residualquantity of ink in the ink cartridge 180 can be detected by mounting theactuator 106 on the ink cartridge 180. The partition wall 212 a preventsthe waving and bubbling of ink.

[0413]FIG. 68 shows a detail around the head member of the ink jetrecording apparatus. In the present embodiment, the ink cartridge 180Ashown in FIG. 57 is used. However, the ink cartridge in any of the inkcartridge shown in FIG. 58 to FIG. 64 also can be used. Furthermore, theink cartridge of the other form also can be used. The ink jet recordingapparatus has an ink introducing member 182, a holder 184, a head plate186, and a nozzle plate 188. A plurality of nozzle 190, which jet outink, is formed on the nozzle plate 188. The ink introducing member 182has an air supply hole 181 and an ink introducing inlet 183. The airsupply hole 181 supplies air to the ink cartridge 180. The inkintroducing inlet 183 introduces ink from the ink cartridge 180A. Theink cartridge 180A has an air introducing inlet 185 and an ink supplyport 187. The air introducing inlet 185 introduces air from the airsupply hole 181 of the ink introducing member 182. The ink supply port187 supplies ink to the ink introducing inlet 183 of the ink introducingmember 182. By introducing air from the ink introducing member 182 tothe ink cartridge 180, the ink cartridge 180 accelerates the supply ofink from the ink cartridge 180A to the ink introducing member 182. Theholder 184 communicates ink, which is supplied from the ink cartridge180A through the ink introducing member 182, to the head plate 186. Inkis supplied to the head from the ink cartridge 180A through the inkintroducing member 182 and discharged to the recording medium fromnozzle. In this way, the ink jet recording apparatus performs theprinting on the recording medium.

[0414]FIG. 69 is a cross sectional view of an embodiment of an inkcartridge for use with a single color, for example, the black ink as anembodiment of the liquid container according to the present invention.An ink cartridge shown in FIG. 69 is based on the method that detectsthe position of the liquid surface or an existence of liquid inside aliquid container by detecting a resonant frequency by measuring thecounter electromotive force generated by the residual vibration remainedin the vibrating section among the above mentioned method. The actuator106 is used for an embodiment of the liquid censor that detects liquid.The ink cartridge of the embodiment shown in FIG. 69 comprises acontainer 1 which contains liquid K and includes top wall 1030 locatedupside of the liquid surface of ink K, an ink supply port 2 whichsupplies liquid K outside the container 1, an actuator 106 which detectsink consumption status inside the container 1, and a first partitionwall 193 a which partitions at least two ink chamber such that ink K inboth of the ink chamber can communicate with each other inside thecontainer 1.

[0415] At least two ink chambers include a ventilation side ink chamber123 a which communicate with atmosphere and the detecting side inkchamber 123 b. The actuator 106 is mounted on the top wall 1030 of theink chamber 123 b, and a porous member 1000 is provided in the detectionside ink chamber 123 b as a buffer member. A coarse buffer material suchas filter can be used instead of the porous member 1000.

[0416] The airhole 2 c is provided on the top wall 1030 of theventilation side ink chamber 123 a which ventilates with atmosphere. Thecheck valve 228 shown in FIG. 85 can be used for airhole 2 c. However,the form of the airhole 2 c is not limited to the check valve 228 shownin FIG. 85. If ink K is consumed and the container 1 inside decreases,air is introduced to the ventilation side ink chamber 123 a from theoutside of the container 1 by the airhole 2 c, and the airhole 2 c thusprevents the pressure inside the container 1 to be negative. Therefore,with the consumption of ink advanced, air is introduced to theventilation side ink chamber 123 a through the airhole 2 c, and thelevel of liquid surface of ink K decreases.

[0417] The partition wall 193 a is coupled with the top wall 1030 andside wall, not shown in the figure, liquid-tightly. Therefore, even theink is consumed, ink K is sufficiently absorbed in the porous member1000 and filled in the detection side ink chamber 123 b in the container1 until the level of liquid surface of ink K reaches to the lower end193 aa of the partition wall 193 a. When the ink consumption advances,and the level of liquid surface of ink K reaches to the lower end 193 aaof the partition wall 193 a, gas enters to the detection side inkchamber 123 b. The ink k absorbed by the porous member 1000 in thedetection side ink chamber 123 b thereby flows out to the ink supplyport 2, and the medium existed around the actuator 106 changes from inkto atmosphere. Therefore, the actuator 106 can detect that the statusinside the ink cartridge is in ink end status. Thus, it is the lower end193 aa to determine which level of the liquid surface of ink K to be aink end. Furthermore, the volume of the detection side ink chamber 132 bis determined by the position of partition wall 193 a to the top wall1030. Therefore, the ink quantity remains inside the container 1 whendetecting the ink end can be set by the position of the partition wall193 a to the top wall 1030 and the height of the lower end 193 aa in thedirection vertical to the ink surface.

[0418] Here, the case of using an on-carriage type ink jet recordingapparatus, the ink cartridge of which is move together with recordinghead during the scanning process will be considered. If there is nopartition wall 193 a in the container 1, or if no buffer material isprovide around the actuator 106, bubbles may be generated by the wavingof ink, which is caused by the vibration of ink cartridge generated bysuch as the scanning operation during the printing process because theink cartridge moves together with recording head. Then, there is adanger that the actuator 106 may detect mistakenly that there is enoughink in the container 1 if the ink attaches to the actuator 106 by thewaving of ink even if there is little amount of ink in the container 1.Moreover, there is also a danger that the actuator 106 may detectmistakenly that there is no ink if the bubble attaches to the actuator106 even if the ink is filled in the container 1.

[0419] However, according to the embodiment of the liquid container ofthe present embodiment, the partition wall prevents the waving of inkaround the piezoelectric device even when the ink cartridge vibrates bysuch as the scanning operation during the printing process. Bypreventing the waving of ink around the piezoelectric device, thepartition wall 193 a prevents the generation of the bubbles.Furthermore, even the bubbles generate in the ventilation side inkchamber, the partition wall separates the ventilation side ink chamberand the detection side ink chamber. Therefore, the partition wallprevents the bubbles to move close to the actuator 106 and contact withthe actuator 106.

[0420] Moreover, the porous member 1000 is provided on the detectionside ink chamber 123 b to intervene between the actuator 106 and theventilation side ink chamber 123 a. Therefore, even if the bubblesgenerated in the ventilation side ink chamber 123 a enters into thedetection side ink chamber 123 b mistakenly, the porous member 1000prevents the bubbles to move close to the actuator 106 and contact withthe actuator 106.

[0421] Furthermore, because the porous member 1000 is provided in thedetection side ink chamber 123 b, ink inside the detection side inkchamber 123 b does not wave by the vibration of the actuator 106.Therefore, the actuator 106 can reliably and stably detect the inkconsumption status in the container 1.

[0422] The volume of the detection side ink chamber 123 b is preferablyhalf or smaller than half of the volume of the ventilation side inkchamber 123 a. The detection side ink chamber 123 b preferably has awidth in a degree not to arise a capillary force such as to hold ink K.

[0423] The actuator 106 can be used as a means of merely detecting thevibration without vibrating itself.

[0424] There is no limitation of the size, thickness, shape,flexibility, and material for the partition wall of the ink cartridge ofthe embodiment of the liquid container according to the presentembodiment. Therefore, the size of the partition wall can be madefurther larger or smaller. The thickness of the partition wall can bemade further thicker or thinner. Furthermore, the shape of the partitionwall can be square or rectangular. Furthermore, the partition wall canbe made from the hard material or flexible material. For example,material such as plastic, tefron, nylon, polypropylene, or PET can beused for the partition wall. Preferably, the partition wall is made fromthe air-tight or liquid-tight material which does not pass through gasor liquid. Moreover, the container and the partition wall are made fromsame material so that the container and the partition wall can be formedin one body. The manufacturing process of the ink cartridge can therebybe reduced.

[0425] Moreover, there is no limitation of the size, thickness, shape,flexibility, and material for the porous member of the ink cartridge ofthe embodiment of the liquid container according to the presentembodiment. Therefore, the size of the porous member can be made furtherlarger or smaller. The thickness of the porous member can be madefurther thicker or thinner. Furthermore, the shape of the porous membercan be cubic or rectangular parallelepiped.

[0426] Moreover, there is no limitation of the shape of the holeincluded in the porous member. Therefore, for example, the negativepressure or capillary force of the porous member, which includes thehole of spherical shape, can be increased by reducing the size of thehole. On the other hand, the negative pressure or capillary force of theporous member, which includes the hole of spherical shape, can bedecreased by enlarging the size of the hole. Preferably, the porousmember 1000 is made from a flexible material such as sponge. Moreover,it is preferable to set the diameter of hole of the porous member topredetermined diameter so that the porous member can absorb ink from acavity, referring to FIG. 19, which is formed in the actuator 106, andintroduce ink to ink supply port, referring to FIG. 1.

[0427] The porous member 1000 of the embodiment shown in FIG. 69 has ashape of rectangular parallelepiped. The porous member 1000 is filled inthe detection side ink chamber 123 b such that the porous member 1100fills from the periphery of the actuator 106 to the bottom wall 1 awhich is located below the ink surface in the ink cartridge.

[0428] A packing ring 4 and a valve body 6 are provided in the inksupply port 2. Referring to FIG. 70, the packing ring 4 is engaged withthe ink supply needle 32 communicating with a recording head 31, in afluid-tight manner. The valve body 6 is constantly and elasticallycontacted against the packing ring 4 by way of a spring 5. When the inksupply needle 32 is inserted, the valve body 6 is pressed by the inksupply needle 32 so as to open an ink passage, so that ink inside thecontainer 1 is supplied to the recording head 31 via the ink supply port2 and the ink supply needle 32. On an upper wall of the container 1,there is mounted a semiconductor memory means 7 which stores data on inkinside the ink cartridge.

[0429]FIG. 71 is a cross sectional view of a further another embodimentof an ink cartridge as an embodiment of the liquid container accordingto the present invention. An ink cartridge of the present embodiment hasa top wall 1030, which locates upside of the liquid surface of ink K.The actuators 106 are mounted on the top wall 1030 such that theactuator 106 can contacts with ink through the through hole 1 c providedon the top wall 1030. A first partition wall 193 c extends from the topwall 1030 downward to the ink surface. Furthermore, the presentembodiment has a second partition wall 193 d which extends from the topwall 1030 inside the detection side ink chamber 123 b and separates thedetection side ink chamber 123 b at least into two detection side smallink chambers 1123 a and 1123 b such that ink housed in both of thedetection side small ink chamber 1123 a and 1123 b can communicate eachother. The actuator 106 is mounted on the top wall 1030 of each of thedetection side small ink chambers 1123 a and 1123 b, respectively.

[0430] Furthermore, a porous member 1002 and a porous member 1003 areprovided to each of the inside of the detection side small ink chamber1123 a and the detection side small ink chamber 1123 b.

[0431] Because gas is introduced from the airhole 128, ink is consumedfrom the ventilation side ink chamber 123 a, which is near to theairhole 128, to the detection side small ink chamber 1123 b, which isfar from the airhole 128. Therefore, during ink in the ventilation sideink chamber 123 a which is nearest to the airhole 128 is consumed, thedetection side ink chamber 123 b is filled with ink. When the ink levelin the ventilation side ink chamber 123 a reaches to the lower end 193cc of the partition wall 193 c, air enters into the detection side smallink chamber 1123 a, and then the ink in the detection side small inkchamber 1123 a is beginning to be consumed. At this time, ink is filledin the detection side small ink chamber 1123 b. Furthermore, if the inklevel in the detection side small ink chamber 1123 a reaches to thelower end 193 dd of the second partition wall 193 d, air enters into thedetection side small ink chamber 1123 b, and then the ink in thedetection side small ink chamber 1123 b is beginning to be consumed. Inthis way, ink is sequentially consumed from the ventilation side inkchamber 123 a to the detection side small ink chamber 1123 b.

[0432] Because each of the actuators 106 is mounted on the top wall 1030of each of the detection side small ink chambers 1123 a and 1123 b, theactuators 106 can detect the decrease of the ink quantity step by step.Furthermore, the volume of the detection side ink chamber 123 b issmaller than the volume of the ventilation side ink chamber 213 a.Furthermore, the volume of the detection side small ink chamber 1123 aand 1123 b gradually decreases from the detection side small ink chamber1123 a which is near to the airhole 128 to the detection side small inkchamber 1123 b, which is far from the airhole 128. Therefore, the timeinterval of detecting the decrease of the ink quantity graduallydecreases. The frequency of the ink quantity detection can thereby beincreased as the ink end is drawing near.

[0433]FIG. 72 shows further another embodiment of the ink cartridgeusing the actuator 106. An ink cartridge 180A shown in FIG. 72 has apartition wall 212 a which extends downward from the top face 194 c ofthe ink container 194. The container 194 is separated into a ventilationside ink chamber 213 a and a detection side ink chamber 213 b by thepartition wall 212 a. Because lower end 212 aa of the partition wall 212a and the bottom wall 1 a of the container 194 have a predeterminedspace, the ventilation side ink chamber 213 a and the detection side inkchamber 213 b communicates with each other.

[0434] A buffer member 1005 a is provided to block the communicatingport between the ventilation side ink chamber 213 a and the detectionside ink chamber 213 b. A filter-like material, which includes manyholes on its surface, can be used for buffer member 1050 a if the buffermember closes the communicating port. Furthermore, the buffer member canbe porous member. Therefore, the ventilation side ink chamber 213 a andthe detection side ink chamber 123 b communicates each other through thebuffer member 1005 a. Because the buffer member 1005 a is made fromporous material, the buffer material pass through gas and liquid.However, if the buffer member 1005 a holds liquid by the capillaryforce, the buffer member becomes airtight. Therefore, the buffer member1050 a can suppress bubbles to passing through the buffer member 1050 a.Thus, the buffer member 1050 a can prevents the bubbles, which isgenerated in the ventilation side ink chamber 213 a, to enter inside thedetection side ink chamber 213 b and attach to the actuator 106.

[0435] The actuator 106 is mounted on the top wall 194 c of each of theventilation side ink chamber 213 a and the detection side ink chamber213 b. The volume of the detection side ink chamber 213 b is smallerthan the volume of the ventilation side ink chamber 213 a. The volume ofthe detection side ink chamber 213 b is smaller than the half of thevolume of the ventilation side ink chamber 213 a in the ink cartridge ofaccording to the present embodiment.

[0436] A buffer 214 a, that is a concave part for accepting the airbubble which enters to the ink cartridge 180A is formed on the top wall194 c of the detection side ink chamber 213 b. In FIG. 72, the buffer214 a is formed as a concave part overhang upward from the top wall 194c of the container 194. The buffer 214 a accepts the air bubble whichenters into the detection side ink chamber 213 b mistakenly when the inkis filled in the detection side ink chamber 213 b. The buffer 214 athereby prevents the bubbles to attach to the actuator 106. Therefore,the buffer 214 b prevents the malfunction of the actuator 106 to detectthe ink end wrongly by the attaching of air bubble to the actuator 106.Furthermore, the level of ink surface on which the actuator 106 detectsthe ink end can be changed by changing the length of the partition wall212 a. Furthermore, by changing the width between the partition wall 212a and the side wall 194 b, the predetermined ink quantity remained afterthe detection of the ink end can be changed.

[0437] The ink cartridge 180B shown in FIG. 73 fills a porous member1005 b in the detection side ink chamber 123 b of the ink cartridge 180Ashown in FIG. 72. The porous member 1005 b is filled inside thedetection side ink chamber 213 b from the top wall 194 c to the bottomwall 194 a. The porous member 1005 b contacts with the actuator 106.There is a case that the actuator 106 malfunctions by the entering ofthe air inside the detection side ink chamber 213 b when the inkcartridge fall down or when the detection side ink chamber 213 b movesback and forth with the carriage. If the porous member 1005 b isprovided on the detection side ink chamber 213 b, the porous member 1005b captures air to prevent entering of air into the actuator 106.Furthermore, because the porous member 1005 b holds ink, the porousmember 1005 b can prevent the actuator 106 to malfunction as detectingthe ink end status as ink exist status which is caused by attaching ofthe ink on the actuator 106 when the ink container rolls. The inkquantity which can be consumed after the detection of the ink end can bechanged by adjusting the volume of the detection side ink chamber 213 bby changing the width between the side wall 194 b and the partition wall212 a. Furthermore, the level of ink surface on which the actuator 106detects the ink end can be changed by adjusting the height of the lowerend 212 aa of the partition wall 212 a from the ink surface.

[0438]FIG. 74 shows an ink cartridge 180C, the porous member of which isconstituted by two kinds of porous members 1005 c and 1005 d having adifferent hole diameter with each other. The porous member 1005 c islocated closer to the actuator 106 than the porous member 1005 d. Thehole diameter of the porous member 1005 c is larger than the holediameter of the porous member 1005 d. The capillary force of the porousmember 1005 d, which has small hole diameter, is larger than thecapillary force of the porous member 1005 c, which has large holediameter. Therefore, the ink, which once flows from the porous member1005 c to the porous member 1005 d, does not flow backward to the porousmember 1005 c because the capillary force works at the porous member1005 d. Therefore, the porous members 1005 c and 1005 d prevents theattaching of ink to the actuator 106 by the waving of ink and therebyprevents the malfunction of the actuator 106 to detect the ink endstatus as ink exist status. The porous member 1005 c can be formed bythe material which has a lower affinity for liquid than the affinity forliquid of the material which forms the porous member 1005 d.

[0439]FIG. 75 shows a cross section of an ink cartridge 180D which isfurther other embodiment of the ink cartridge 180 using actuator 106.Ribs 1100, which protrudes inside the ink container 194, are provided onthe bottom side of the side wall 194 b of the detection side ink chamber213 b. The porous member 1005 b which is provided inside the detectionside ink chamber 213 b is gradually compressed by the ribs 1100 suchthat the area of the cross section on the horizontal plane of the porousmember 1005 b gradually decreases downwards along the verticaldirection. Therefore, the hole diameter of the porous member 1005 bdecreases gradually in the direction downward to the ink surface.Because the hole diameter of the lower part of the porous member 1005 breduced by the ribs 1100, the ink, which once flows into the lower partof the porous member 1005 b does not flow backward to the upside of theporous member 1005 b by the capillary force. Furthermore, the porousmember 1005 b of the present embodiment prevents ink to attach to theactuator 106, which is mounted on the top wall 194 c, by the waving ofink. Therefore, the malfunction of the actuator 106 to detect the inkend status as the ink exist status can be prevented.

[0440] FIGS. 76(A) and 76(B) shows further another embodiment of the inkcartridge using actuator 106. FIG. 76(A) is a cross sectional view alongthe longitudinal direction of a ink cartridge 180E. FIG. 76(B) shows B-Bcross sectional view of the ink cartridge 180E shown in FIG. 76(A). Ataper 1110 is provided on the lower side of the side wall of thedetection side ink chamber 213 b. The width of the detection side inkchamber 213 b gradually narrows downward along the vertical direction bythe taper 1110. Therefore, the porous member 1005 b is compressedgradually by the taper 1110 such that the area of the cross section onthe horizontal plane of the porous member 1005 b gradually decreasesdownwards along the vertical direction. Therefore, lower side of thehole diameter of the porous member 1005 b gradually becomes smaller thanthe upper side of the hole diameter of the porous member 1005 b by thetaper 1110. Because the hole diameter of the lower part of the porousmember 1005 b reduced by the taper 1110, the ink, which once flows intothe lower part of the porous member 1005 b does not flow backward to theupside of the porous member 1005 b by the capillary force. Furthermore,the porous member 1005 b of the present embodiment prevents ink toattach to the actuator 106, which is mounted on the top wall 194 c, bythe waving of ink. Therefore, the malfunction of the actuator 106 todetect the ink end status as the ink exist status can be prevented.

[0441]FIG. 77 shows further another embodiment of the ink cartridgeusing actuator 106. An ink cartridge 180F shown in FIG. 77 has apartition wall 212 c which is sloped toward the ink surface. A porousmember 1105 e is filled in the detection side ink chamber 213 b. Thepartition wall 212 c extends from a top wall 194 c. The distance betweenthe side wall 194 b of the ink cartridge 180C and the partition wall 212c gradually narrows toward downside. Therefore, the porous member 1005 eis compressed gradually by the partition wall 212 c such that the areaof the cross section on the horizontal plane of the porous member 1005 bgradually decreases toward downside. Therefore, lower side of the holediameter of the porous member 1005 e gradually becomes smaller than theupper side of the hole diameter of the porous member 1005 e by thepartition wall 212 c. Because the hole diameter of the lower part of theporous member 1005 e is reduced by the partition wall 212 c, the ink,which once flows into the lower part of the porous member 1005 e doesnot flow backward to the upside of the porous member 1005 e by thecapillary force. Furthermore, the porous member 1005 e of the presentembodiment prevents ink to attach to the actuator 106, which is mountedon the top wall 194 c, by the waving of ink. Therefore, the malfunctionof the actuator 106 to detect the ink end status as the ink exist statuscan be prevented.

[0442] Moreover, gas existed in the ventilation side ink chamber 213 ais difficult to enter into the detection side ink chamber 213 b.Therefore, the malfunction caused by the attaching of bubble to theactuator 106 can be further prevented. Furthermore, a gap is providedbetween the lower end 212 cc and the bottom wall 2 a of the inkcartridge 180F. A capillary force, which can hold ink, does not work onthe gap provided between the lower end 212 cc and the side wall 194 b.

[0443]FIG. 78 shows further another embodiment of the ink cartridgeusing the actuator 106. An ink cartridge 180G shown in FIG. 78 has apartition wall 212 b which is formed in L-shape. The partition wall 212b extends from a top wall 194 c. A lower end 212 bb of the partitionwall 212 b is longer than the lower end 212 aa of the partition wall 212a in the embodiment shown in FIG. 72 to FIG. 77. A porous member 1005 fis filled in the detection side ink chamber 213 b.

[0444] A porous member 1005 g, which is a bottom part of porous member1005 f, is sandwiched and compressed by the lower end 212bb and the sidewall 194 b. Therefore, the hole diameter of the porous member 1005 g issmaller than the hole diameter of the porous member 1005 f. Thus, thehole diameter of the porous member decreases from the porous member 1005f, which locates nearby the actuator 106, to the porous member 1005 gand further to porous member 1005 h. The hole diameter of the porousmember 1005 f thereby decreases step by step downward to the inksurface. Therefore, the ink, which once flows into the lower part of theporous member 1005 f does not flow backward to the upside of the porousmember 1005 f by the capillary force. Furthermore, the porous member1005 f of the present embodiment prevents ink to attach to the actuator106, which is mounted on the top wall 194 c, by the waving of ink.Therefore, the malfunction of the actuator 106 to detect the ink endstatus as the ink exist status can be prevented.

[0445] Moreover, the bottom end 212 bb is longer than the lower end 212aa of the partition wall 212 a of the embodiments shown in FIG. 72 toFIG. 77. Therefore, gas existed in the ventilation side ink chamber 213a is difficult to enter into the detection side ink chamber 213 b.Therefore, the malfunction of the actuator 106 to detects the ink endwrongly caused by the attaching of bubble to the actuator 106 can befurther prevented. Furthermore, a gap is provided between the lower end212 bb and the bottom wall 2 a. A capillary force, which can hold ink,does not work on the gap provided between the lower end 212 bb and thebottom wall 2 a.

[0446]FIG. 79 shows further another embodiment of the ink cartridge 180.An ink cartridge 180H shown in FIG. 79 has a first partition wall 212 dwhich extends downward from the top face 194 c of the ink container 194.Furthermore, a second wall extends from the first partition wall 212 dtoward the side wall 194 b substantially parallel to the ink surface.The container 194 is separated into a ventilation side ink chamber 213 aand a detection side ink chamber 213 b by the first partition wall 212d. Furthermore, the second partition wall 212 e separates the detectionside ink chamber into a first detection side ink chamber 213 c and asecond detection side ink chamber 213 d. A gap is provided between thebottom wall 2 a and the lower end 212 dd of the first partition wall 212d. Furthermore, a gap is provided between the side wall 194 b and theone end 212 ee of the second partition wall 212 e. A concave part isprovided on a part of top wall 194 c to form a buffer 214 a whichaccepts the bubble. Furthermore, porous member 1005 i is filled insidethe first detection side small ink chamber 213 c. One end 212 ee of thesecond partition wall 212 e, which extends toward the side wall 194 b,extends until to the position where just under the buffer 214 b.

[0447] Therefore, first, the first partition wall 212 d prevents theentering of bubble into the first detection side ink chamber 213 c. Ifthe bubble enters into the detection side ink chamber 213 c mistakenly,the bubble is absorbed by the porous member 1005 i. Furthermore, if thebubble reaches to the second partition wall 212 e, the bubble isintroduced to the position which is just under the buffer 214 a by thesecond partition wall 212 e. Therefore, the bubble is caught by thebuffer 214 a. Therefore, the malfunction of the actuator 106 to detectsthe ink end wrongly by the attaching of bubble to the actuator 106,which is provided in the second detection side ink chamber 213 d, can befurther prevented.

[0448]FIG. 80 shows further another embodiment of the ink cartridge 180.An ink cartridge 180I shown in FIG. 80 has a partition wall 212 a assame as the partition wall 212 a of FIG. 72. The partition wall 212 aextends downward from the top face 194 c of the ink container 194. Thecontainer 194 is separated into a ventilation side ink chamber 213 a anda detection side ink chamber 213 b by the partition wall 212 a. A gap isprovided between the bottom wall 1 a and the partition wall 212 a. Aporous member 1005 b is provided inside the detection side ink chamber213 b. Furthermore, a concave part is provided on a part of top wall 194c to form a buffer 214 b which accepts the bubble. A tapered face 1040is provided between the buffer 214 b and the actuator 106.

[0449] Therefore, first, the partition wall 212 a prevents the enteringof bubble into the detection side ink chamber 213 b. If the bubbleenters into the detection side ink chamber 213 b mistakenly, the bubbleis absorbed by the porous member 1005 b. If the bubble reaches to theupper side of the detection side ink chamber 213 b, the bubble isdirectly caught by the buffer 214 a or introduced to the buffer 214 balong the tapered face 1040. Therefore, the malfunction of the actuator106 to detects the ink end wrongly by the attaching of bubble to theactuator 106 can be further prevented. The shape and size of the buffercan be other arbitrary shape and size.

[0450] Moreover, the second partition wall 212 e in the embodiment shownin FIG. 79 can be provided on the ink cartridge 180I of the embodimentshown in FIG. 80 such that the second partition wall 212 e extends fromthe first partition wall 212 a toward the side wall 214 b in thedirection parallel to the ink surface. In this case, one end 212 ee ofthe second partition wall 212 e is extended to the position just underthe taper face 1040.

[0451]FIG. 82 shows further another embodiment of the ink cartridge 180using actuator 106. An ink cartridge 180K shown in FIG. 82 has aprotruding part 214 f, which protrudes inside the container 194, on apart of the top wall 194 c. The actuator 106 is mounted on the bottompart of the protruding part 214 f. A partition wall 212 f extendsdownward from the top face 194 c. A buffer 214 c is provided for each ofthe position between the actuator 106 and the partition wall 212 a andbetween the actuator 106 and the side wall 194 b. Therefore, theperiphery of the actuator 106 is surrounded by the buffer 214 c. Aporous member 1005 b is provided inside the detection side ink chamber213 b. By providing the actuator 106 on the protruding part 214 f,positioning for mounting the actuator 106 on the ink cartridge 180Jbecomes easier when manufacturing the ink cartridge 180J.

[0452]FIG. 82 shows further another embodiment of the ink cartridge 180using actuator 106. An ink cartridge 180K shown in FIG. 82 has apartition wall 212 a extends downward from the top face 194 c. Thecontainer 194 is separated into a ventilation side ink chamber 213 a anda detection side ink chamber 213 b by the partition wall 212 g. Unevenpart is provided on the top wall 194 c, and two actuators 106 aremounted on the protruding part which protrudes inside the detection sideink chamber 213 b. The concave part of the top wall 194 c works as abuffer 214 c which accepts bubble. Furthermore, a porous member 1005 bis provided inside the detection side ink chamber 213 b. By providingtwo actuators 106 on the protruding part 214 f, detecting the inkconsumption status mistakenly can be prevented. The number of theactuators 106 can be more than three. Moreover, as shown in FIG. 81,positioning for mounting the actuator 106 on the ink cartridge 180Kbecomes easier when manufacturing the ink cartridge 180K. The number ofuneven part and the number of the actuator 106 can be further increased.

[0453]FIG. 83 shows further other embodiment of the ink cartridge 180using actuator 106. The ink cartridge 180M shown in FIG. 83 has aplurality of partition walls 212 f, 212 g, 212 h, and 212 i, each ofwhich extends downward from the top face 194 c of the ink container 194.The partition wall 212 f is first partition wall, and the partitionwalls 212 g, 212 h, and 212 i are the second partition walls. Becauseeach of lower ends 212 ff, 212 gg, 212 hh, and 212 ii of each of thepartition walls 212 f, 212 g, 212 h, and 212 i and the bottom wall 2 aof the container 194 have a predetermined gap, the bottom part of thecontainer 194 communicates with each other. The ink cartridge 180M has aventilation side ink chamber 213 a and a plurality of detection sidesmall ink chambers 213 f, 213 g, 213 h, and 213 i separated by the eachof plurality of partition walls 212 f, 212 g, 212 h and 212 i. Thebottom part of a plurality of the detection side small ink chambers 213f, 213 g, 213 h, and 213 i communicate with each other. Each of theactuators 106 f, 106 g, 106 h, and 106 i is mounted on the top face 194c of each of the plurality of the detection side small ink chambers 213f, 213 g, 213 h, and 213 i, respectively. Each of the actuators 106 f,106 g, 106 h, and 106 i is arranged on substantially center of the topface 194 c of each of the plurality of the detection side small inkchambers 213 f, 213 g, 213 h, and 213 i, respectively.

[0454] The volume of the ventilation side ink chamber 213 a, and thedetection side small ink chamber 213 f, 213 g, 213 h, and 213 i aregradually decreases as the distance from the airhole 128 increases tothe inner side of the ink container 194. Therefore, the volume of theink chambers gradually decreases in the order from the ventilation sideink chamber 213 a, the detection side small ink chamber 213 f, 213 g,213 h, and 213 i. Therefore, the interval of the mounting position ofthe actuator 106 is wider on the airhole 128 side and becomes narroweras the distance from the airhole increases to the inner side of the inkcontainer 194.

[0455] Furthermore, each of the porous members 1005 f, 1005 g, 1005 hand 1005 i are filled in the each of the detection side small inkchambers 213 f, 213 g, 213 h, and 213 i. The each of the porous members1005 f, 1005 g, 1005 h and 1005 i are filled from the detection sidesmall ink chambers 213 f, which is near to the airhole 128, to thedetection side small ink chamber 213 i, which is far from the airhole128, sequentially. The porous members are designed such that the holediameter increases in the order from the porous member 1005 f, 1005 g,1005 h and 1005 i. The porous members can be formed such that theaffinity for ink decreases in the order from the porous member 1005 f,1005 g, 1005 h and 1005 i.

[0456] Because gas is introduced from the airhole 128, ink is consumedfrom the ventilation side ink chamber 213 a of the airhole 128 side tothe detection side ink chamber 213 i. For example, the ink in theventilation side ink chamber 213 a which is nearest to the airhole 128is consumed, and during the ink level of the ventilation side inkchamber 213 a decreases, the other detection side small ink chambers 213f, 213 g, 213 h, and 213 i are filled with ink. When the ink level inthe ventilation side ink chamber 213 a reaches to the lower end 212 ffof the partition wall 212 f, air enters into the detection side smallink chamber 213 f, and then the ink in the detection side small inkchamber 213 f is beginning to be consumed. The ink level in thedetection side small ink chamber 213 f thereby begin to decrease. Atthis time, ink is filled in the detection side small ink chambers 213 g,213 h, and 213 i. In this way, ink is sequentially consumed from theventilation side ink chamber 213 a to the detection side small inkchamber 213 i.

[0457] Furthermore, the porous members are designed such that the holediameter increases in the order from the porous members 1005 f, 1005 g,1005 h and 1005 i. Therefore, ink is consumed in the order from thedetection side small ink chamber 213 f which is relatively near to theairhole 128 to the detection side small ink chamber 213I which is farfrom the airhole 128, sequentially. Moreover, the porous members 1005 f,1005 g, 1005 h and 1005I prevent ink to flow back from the detectionside small ink chamber 213 f to the detection side small ink chamber 213i.

[0458] In the present embodiment, each of the actuators 106 f, 106 g,106 h, and 106 i is mounted on the top wall 194 c of each of thedetection side small ink chambers 213 f, 213 g, 213 h, and 213I withinterval. Therefore, the actuators 106 f, 106 g, 106 h, and 106 i candetect the decrease of the ink quantity step by step. Furthermore, thevolume of the ink chambers decreases from the ventilation side inkchamber 213 a to the detection side small ink chamber 213 i gradually.Therefore, the time interval of detecting the decrease of the inkquantity gradually decreases. Therefore, the frequency of the inkquantity detection can be increased as the ink end is drawing near.

[0459] Furthermore, each of the volume of the detection side small inkchamber can be changed by changing the length of the partition wall asin the embodiment shown in FIG. 87.

[0460]FIG. 84 shows further other embodiment of the ink cartridge 180using actuator 106. In the ink cartridge 180N shown in FIG. 84, porousmembers 1006 f, 1006 g, 1006 h and 1006 i are provided in the inkcartridge 180N such that each porous members 1006 f, 1006 g, 1006 h and1006 i closes the each of the communication port of the ventilation sideink chamber 213 a, the detection side small ink chambers 213 f, 213 g,213 h, and 213 i. Each of the ventilation side ink chamber 213 a, thedetection side small ink chambers 213 f, 213 g, 213 h, and 213 icommunicates each other through the porous members 1006 f, 1006 g, 1006h and 1006 i. Therefore, the porous members prevent the bubble, which isgenerated in the ink container 194, to enter into the ventilation sideink chamber 213 a, the detection side small ink chambers 213 f, 213 g,213 h, and 213 i. Therefore, even if the bubble generates in one of thedetection side ink chambers, and one of the actuators 106 f, 106 g, 106h, and 106 i detects the ink end status mistakenly, the other actuators106 f, 106 g, 106 h, and 106 i do not detect the ink end statusmistakenly.

[0461]FIG. 85 shows further other embodiment of the ink cartridge usingthe actuator 106. The ink cartridge 220A shown in FIG. 85 has a firstpartition wall 222 provided such that it extends downward from the topwall of the ink cartridge 220A. Because there is a predetermined spacebetween the lower end of the first partition wall 222 and the bottomwall 3 a of the ink cartridge 220A, ink can flows into the ink supplyport 230 through the bottom wall 3 a of the ink cartridge 220A. A secondpartition wall 224 is formed such that the second partition wall 224extends upward from the bottom wall 3 a of the ink cartridge 220A on themore ink supply port 230 side of the first partition wall 222. Becausethere is a predetermined space between the upper end of the secondpartition wall 224 and the top wall 221 of the ink cartridge 220A, inkcan flows into the ink supply port 230 through the top wall 221 of theink cartridge 220A.

[0462] A ventilation side ink chamber 225 a is formed relatively near tothe airhole 233. On the other hand, a detection side ink chamber 225 bis formed relatively far from the airhole 233. By the second partitionwall 224, the detection side ink chamber 225 b and a detection sidesmall ink chamber 227 are formed. The detection side small ink chamber227 is formed between the first partition wall 222 and the secondpartition wall 224. The detection side small ink chamber 227 is formedby providing a gap, which can generate the capillary phenomenon, betweenthe first partition wall 222 and the second partition wall 224.Therefore, the ink in the ventilation side ink chamber 225 a iscollected to the detection side small ink chamber 227 by the capillaryforce of the detection side small ink chamber 227. Therefore, thedetection side small ink chamber 227 can prevent that the air bubble toenter into the detection side ink chamber 225 b. Furthermore, the inklevel in the detection side ink chamber 225 b can decrease steadily andgradually.

[0463] Moreover, a porous member 1005 g is provided inside the detectionside ink chamber 225 b. The volume of the ventilation side ink chamber225 a is larger than the volume of the detection side ink chamber 225 b.Because the ventilation side ink chamber 225 a is formed closer to theairhole 223 than the detection side small ink chamber 225 b, the ink inthe detection side small ink chamber 225 b is consumed after the ink inthe ventilation side ink chamber 225 a is consumed. Furthermore, thewaving of ink inside the detection side small ink chamber 225 b isprevented by providing the porous member 1005 g inside the detectionside small ink chamber 225 b. Moreover, the porous member 1005 gprevents the bubble, which is entered from the ink supply port 230, toattach to the actuator 106.

[0464] Furthermore, the capillary force of the porous member 1005 g isgreater than the capillary force of the detection side small ink chamber227. The porous member 1005 g thereby prevents ink to flow back from theink supply port 230 to the ventilation side small ink chamber 225 a. Thecapillary force of the porous member 1005 g can be increased byadjusting the hole diameter. Moreover, the capillary force of the porousmember 1005 g can be increased by compressing the porous member 1005 g.

[0465] A airhole 233 is provided on the top wall of the ink cartridge220A. Moreover, a check valve 228 is provided on the airhole 233 forpreventing the leaking of ink from the airhole 233. The leaking of inkoutside the ink cartridge 220A caused by the rolling of the inkcartridge 220A can be prevented by the check valve 228. Furthermore, theevaporation of ink from the airhole 233 of the ink cartridge 220A can beprevented by providing the check valve 228 on the top face of the inkcartridge 220A. If ink in the ink cartridge 220A is consumed, andnegative pressure inside the ink cartridge 220A exceeds the pressure ofthe check valve 228, the check valve 228 opens and introduces air intothe ink cartridge 220A. Then the check valve 228 closes to acceleratethe drainage of ink from the ink cartridge 220A.

[0466] Here, a piezoelectric device as an embodiment of a liquid censorwill be explained. The piezoelectric device, or actuator, detects astate of the liquid inside a liquid container by utilizing vibrationphenomena. The state of the liquid includes whether or not the liquid inthe liquid container is empty, amount of the liquid, level of theliquid, types of the liquid and combination of liquids. Several specificmethods realizing for detection of the state of the liquid inside theliquid container utilizing vibration phenomena are considered. Forexample, a method is considered in which the medium and the change ofits state inside the liquid container are detected in such a manner thatan elastic wave generating device generates an elastic wave inside theliquid container, and then the reflected wave which is thus reflected bythe liquid surface or a wall disposed counter thereto is captured. Thereis another method in which a change of acoustic impedance is detected byvibrating characteristics of a vibrating object. As a method utilizingthe change of the acoustic impedance, a vibrating portion of apiezoelectric device or an actuator having a piezoelectric elementtherein is vibrated. Thereafter, a resonant frequency or an amplitude ofthe back electromotive force waveform is detected by measuring the backelectromotive force which is caused by residual vibration which remainsin the vibrating portion, so as to detect the change of the acousticimpedance. As another method utilizing the change of the acousticimpedance, the impedance characteristic or admittance characteristic ofthe liquid is measured by a measuring apparatus such as an impedanceanalyzer and a transmission circuit, so that the change of a currentvalue or a voltage value, or the change of the current value or voltagevalue due to the frequency caused by the vibration given to the liquidis measured. In the present embodiment, the actuator 106 can detect theliquid status inside the liquid container by any method mentioned above.

[0467]FIG. 86 shows further other embodiment of the ink cartridge 180.FIG. 86 shows a cross section of an ink cartridge 180P. Thesemiconductor memory device 7 and the actuator 106 are formed on thesame circuit board 610 in the ink cartridge 180P.

[0468] A different-type O-ring 614 is mounted on the side wall 194 bsuch that the different-type O-ring 614 surrounds the actuator 106. Aplurality of caulking part 616 is formed on the side wall 194 b tocouple the circuit board 610 with the container 194. By coupling thecircuit board 610 with the container 194 using the caulking part 616 andpushing the different-type O-ring 614 to the circuit board 610, thevibrating region of the actuator 106 can contacts with ink, and at thesame time, the inside of the ink cartridge is sealed from outside of theink cartridge.

[0469] A terminals 612 are formed on the semiconductor memory device 7and around the semiconductor memory device 7. The terminal 612 transferthe signal between the semiconductor memory device 7 and outside the inkjet recording apparatus. The semiconductor memory device 7 can beconstituted by the semiconductor memory which can be rewritten such asEEPROM. Because the semiconductor memory device 7 and the actuator 106are formed on the same circuit board 610, the mounting process can befinished at one time during mounting the semiconductor memory device 7and the actuator 106 on the ink cartridge 180P. Moreover, the workingprocess during the manufacturing of the ink cartridge 180C and therecycling of the ink cartridge 180P can be simplified. Furthermore, themanufacturing cost of the ink cartridge 180P can be reduced because thenumbers of the parts can be reduced.

[0470] The actuator 106 detects the ink consumption status inside thecontainer 194. The semiconductor memory device 7 stores the informationof ink such as residual quantity of ink detected by the actuator 106.That is, the semiconductor memory device 7 stores the informationrelated to the characteristic parameter such as the characteristic ofink and the ink cartridge used for the actuator 106 when detecting theink consumption status. The semiconductor memory device 7 previouslystores the resonant frequency of when ink inside the container 194 isfull, that is, when ink is filled in the container 194 sufficiently, orwhen ink in the container 194 is end, that is, ink in the container 194is consumed, as one of the characteristic parameter. The resonantfrequency when the ink inside the container 194 is full status or endstatus can be stored when the ink container is mounted on the ink jetrecording apparatus for the first time. Moreover, the resonant frequencywhen the ink inside the container 194 is full status or end status canbe stored during the manufacturing of the container 194. Because theunevenness of the detection of the residual quantity of ink can becompensated by storing the resonant frequency when the ink inside thecontainer 194 is full status or end status in the semiconductor memorydevice 7 previously and reading out the data of the resonant frequencyat the ink jet recording apparatus side, it can be accurately detectedthat the residual quantity of ink is decreased to the reference value.

[0471]FIG. 87 shows further other embodiment of the ink cartridge 180.The ink cartridge 180Q shown in FIG. 87 has a plurality of partitionwalls 212 p, 212 q, and 212 r. The partition walls 212 p, 212 q, and 212r separates the ink container 194 into the ventilation side ink chamber213 a and the detection side small ink chamber 213 p, 213 q, and 213 r.The partition wall 212 p is the first partition wall, and the partitionwalls 212 q and 212 r are the second partition walls. Each of porousmembers 1005 p, 1005 q, and 1005 r are provided in the each of thedetection side small ink chamber 213 p, 213 q, and 213 r. Furthermore,each of partition walls 212 p, 212 q, and 212 r are provided on the topwall 194 c with substantially equal intervals. Furthermore, each of thepartition walls 212 p, 212 q, and 212 r extends from the top wall 194 ctoward the bottom wall 2 a. Each of the partition walls 212 p, 212 q,and 212 r have different length. Moreover, the length of the partitionwalls 212 p, 212 q, and 212 r increases in the order of the partitionwall 212 p, 212 q, and 212 r. Therefore, even the interval between theeach of the partition walls 212 p, 212 q, and 212 r is different, thevolume of the each of the detection side small ink chambers aredifferent with each other.

[0472] Because the length of each of the partition walls 212 p, 212 q,and 212 r increases with the increase of the distance from the airhole128, gas is most difficult to enter into the detection side small inkchamber 213 r which is farthest from the airhole 128. Therefore, theactuator 106 r can detect the ink existence most accurately among theactuators 106 p, 106 q, and 106 r which is mounted on the each of thedetection side small ink chamber 213 p, 213 q, and 213 r.

[0473]FIG. 88 shows an embodiment around a recording head of part of theink cartridge and an ink jet recording apparatus which uses the actuator106. In the present embodiment, the ink cartridge 180A shown in FIG. 72is used. However, the ink cartridge in any of the ink cartridge shown inFIG. 73 to FIG. 84 also can be used. Furthermore, the ink cartridge ofthe other form also can be used. A plurality of ink cartridges 180A ismounted on the ink jet recording apparatus which has a plurality of inkintroducing members 182 and a holder 184 each corresponding to the eachof ink cartridge 180, respectively. Each of the plurality of inkcartridges 180A contains different types of ink, for example, differentcolor of ink. The actuator 106, which detects at least acousticimpedance, is mounted on the each of top wall of the plurality of inkcartridge 180A. The actuator 106, a partition wall 212 a, and a porousmember 1005 b are provided for each top wall of the plurality of inkcartridge 180A. The residual quantity of ink in the ink cartridge 180can be detected by mounting the actuator 106 on the ink cartridge 180.The partition wall 212 a prevents the waving and bubbling of ink.

[0474]FIG. 89 shows a detail around the head member of the ink jetrecording apparatus. In the present embodiment, the ink cartridge 180Ashown in FIG. 72 is used. However, the ink cartridge in any of the inkcartridge shown in FIG. 73 to FIG. 84 also can be used. Furthermore, theink cartridge of the other form also can be used. The ink jet recordingapparatus has an ink introducing member 182, a holder 184, a head plate186, and a nozzle plate 188. A plurality of nozzle 190, which jet outink, is formed on the nozzle plate 188. The ink introducing member 182has an air supply hole 181 and an ink introducing inlet 183. The airsupply hole 181 supplies air to the ink cartridge 180. The inkintroducing inlet 183 introduces ink from the ink cartridge 180A. Theink cartridge 180A has an air introducing inlet 185 and an ink supplyport 187. The air introducing inlet 185 introduces air from the airsupply hole 181 of the ink introducing member 182. The ink supply port187 supplies ink to the ink introducing inlet 183 of the ink introducingmember 182. By introducing air from the ink introducing member 182 tothe ink cartridge 180, the ink cartridge 180 accelerates the supply ofink from the ink cartridge 180A to the ink introducing member 182. Theholder 184 communicates ink, which is supplied from the ink cartridge180A through the ink introducing member 182, to the head plate 186. Inkis supplied to the head from the ink cartridge 180A through the inkintroducing member 182 and discharged to the recording medium fromnozzle. In this way, the ink jet recording apparatus performs theprinting on the recording medium.

[0475]FIG. 90 is a cross sectional view of an embodiment of an inkcartridge for use with a single color, for example, the black ink. Inthe ink cartridge shown in FIG. 90, the detection method implemented isbased on a method, among methods described above, in which the positionof the liquid surface in the liquid container and whether or not theliquid is empty are detected by receiving the reflected wave of theelastic wave. As a means for generating and receiving the elastic wave,an elastic wave generating device 3 is utilized. An ink supply port 2which comes in contact with an ink supply needle of the recordingapparatus in a sealed manner is provided in a container 1 which housesthe ink. In an outside portion of a bottom face 1 a of the container 1,the elastic wave generating device 3 is mounted such that the elasticwave can be communicated, via the container, to the ink inside thecontainer. In order that at a stage at which the ink K is almost usedup, i.e. at the time when the ink becomes an ink-end state, the transferof the elastic wave can change from the liquid to the gas, the elasticwave generating device 3 is provided in a slightly upward position fromthe ink supply port 2. Moreover, an elastic wave receiving means may beseparately provided instead, so that the elastic wave generating device3 is used as an elastic wave generating device only.

[0476] A packing ring 4 and a valve body 6 are provided in the inksupply port 2. Referring to FIG. 91, the packing ring 4 is engaged withthe ink supply needle 32 communicating with a recording head 31, in afluid-tight manner. The valve body 6 is constantly and elasticallycontacted against the packing ring 4 by way of a spring 5. When the inksupply needle 32 is inserted, the valve body 6 is pressed by the inksupply needle 32 so as to open an ink passage, so that ink inside thecontainer 1 is supplied to the recording head 31 via the ink supply port2 and the ink supply needle 32. On an upper wall of the container 1,there is mounted a semiconductor memory means 7 which stores data on inkinside the ink cartridge.

[0477] Furthermore, a porous member 1050 is provided inside thecontainer 1. A gap is provided between the porous member 1050 and theelastic wave generating device 3 to form an ink layer. By providing theporous member 1050 inside the container 1, the porous member 1050prevents the waving or bubbling of ink inside the container 1 when theink cartridge moves together with the recording head by the scanningoperation during the printing process. Therefore, the bubble and wave ofink is difficult to generate around the elastic wave generating device3, the elastic wave generating device 3 can accurately detect the inkconsumption status.

[0478] Furthermore, the hole diameter of porous member 1050 is set suchthat the porous member 1050 does not absorbs ink existed in the inklayer 1060 when the ink surface reaches to the ink layer 1060 by theconsumption of ink inside the container 1. In other words, the porousmember 1050 is designed such that the capillary force works in theporous member 1050 does not hold ink in the container 1. Therefore, inkdoes not remain in the porous member 1050 by its own weight and remainsin the ink layer 1060 when the ink inside the container 1 is in an inknear end status.

[0479] An airhole, not shown in the figure, is provided on the container1. The airhole is provided on the upper side of the ink surface tocommunicate with outside of container 1. Air is introduced inside thecontainer 1 by the airhole, and ink flows downward by its own weightwith advance of ink consumption. The residual ink thereby stays in theink layer 1060. Because the porous member 1050 is provided inside thecontainer 1, the elastic wave generating device 3 can detect the inkquantity only when the ink status is near to the ink end if the width ofthe ink layer is small. However, ink does not wave by providing theporous member 1050 in the container 1. Therefore, the elastic wavegenerating device 3 can detect the ink surface accurately when the inksurface inside the container 1 reaches to the lower end of the porousmember 1050, and ink surface exists within the ink layer 1060.

[0480] Moreover, the width of the gap between the porous member 1050 andthe elastic wave generating device 3 is not limited. To suppress thebubbling of ink as much as possible, the width of ink layer 1060 isreduced by providing the porous member 1050 on lower side of thecontainer 1. If the width of the ink layer 1060 is small, the elasticwave generating device 3 can detect the ink quantity only when the inkstatus is near to the ink end. However, ink does not wave inside thecontainer 1. Therefore, the elastic wave generating device 3 canaccurately detect the ink quantity and existence of ink when the inkconsumption status is near to the ink end status. Therefore, the porousmember 1050 is preferably located nearby the elastic wave generatingdevice 3 without limiting the width of gap between the porous member1050 and elastic wave generating device 3. Moreover, even the bubble ofink generates, because the bubble of ink is absorbed in the porousmember 1050, the bubble does not stays around the elastic wavegenerating device 3. The porous member 1050 thereby prevents the elasticwave generating device 3 to detect the ink consumption statusmistakenly.

[0481]FIG. 91 is a cross sectional view showing an embodiment of a majorpart of the ink-jet recording apparatus suitable for the ink cartridgeshown in FIG. 90. A carriage 30 capable of reciprocating in thedirection of the width of the recording paper is equipped with a subtankunit 33, while the recording head 31 is provided in a lower face of thesubtank unit 33. Moreover, the ink supply needle 32 is provided in anink cartridge mounting face side of the subtank unit 33.

[0482] While the recording apparatus is operating, a drive signal issupplied to the elastic wave generating device 3 at a detection timingwhich is set in advance, for example, at a certain period of time. Theelastic wave generated by the elastic wave generating device 3 istransferred to the ink by propagating through the bottom face 1 a of thecontainer 1 so as to be propagated to the ink.

[0483] By adhering the elastic wave generating device 3 to the container1, since a process of embedding electrodes for use in detecting theliquid surface is unnecessary in the course of forming the container 1,an injection molding process can be simplified and the leakage of theliquid from a place in which the electrodes are supposedly embedded canbe avoided, thus improving the reliability of the ink cartridge.

[0484] Furthermore, a porous member 1050 is provided inside thecontainer 1. By providing the porous member 1050 inside the container 1,the porous member 1050 prevents the waving or bubbling of ink inside thecontainer 1 when the ink cartridge moves together with the recordinghead by the scanning operation during the printing process. Because thebubble and wave of ink is difficult to generate around the elastic wavegenerating device 3, the elastic wave generating device 3 can accuratelydetect the ink consumption status.

[0485]FIG. 92 is a detailed cross sectional view of a subtank unit 33.The subtank unit 33 comprises the ink supply needle 32, the ink chamber34, a flexible valve 36 and a filter 37. In the ink chamber 34, the inkis housed which is supplied from the ink cartridge via ink supply needle32. The flexible valve 36 is so designed that the flexible valve 36 isopened and closed by means of the pressure difference between the inkchamber 34 and the ink supply passage 35. The subtank unit 33 is soconstructed that the ink supply passage 35 is communicated with therecording head 31 so that the ink can be supplied up to the recordinghead 31.

[0486] Referring to FIG. 91, when the ink supply port 2 of the container1 is inserted through the ink supply needle 32 of the subtank unit 33,the valve body 6 recedes against the spring 5, so that an ink passage isformed and the ink inside the container 1 flows into the ink chamber 34.At a stage where the ink chamber 34 is filled with ink, a negativepressure is applied to a nozzle opening of the recording head 31 so asto fill the recording head with ink. Thereafter, the recording operationis performed.

[0487] When the ink is consumed in the recording head 31 by therecording operation, a pressure in the downstream of the flexible valve36 decreases. Then, the flexible valve 36 is positioned away from avalve body 38 so as to become opened. When the flexible valve 36 isopened, the ink in the ink chamber 34 flows into the recording head 31through the ink passage 35. Accompanied by the ink which has flowed intothe recording head 31, the ink in the container 1 flows into the subtankunit 33 via the ink supply needle 32.

[0488] According to the embodiment shown in FIGS. 91 and 92, the elasticwave generating device 3 and the porous member 1050 are provided also inthe subtank unit 33. The porous member 1050 is provided nearby theelastic wave generating device 3. A gap is provided to form a ink layer1060 between the elastic wave generating device 3 and the porous member1050.

[0489] The elastic wave generating device 3 detects the ink quantity orexistence of ink inside the subtank unit 33. In case of the presentembodiment, because the porous member 1050 is provided inside thesubtank unit 33, if the width of the ink layer 1060 becomes small, theelastic wave generating device 3 can detect the ink quantity only whenthe ink status is near to the ink end. However, ink does not wave insidethe container 1 because the porous member 1050 is provided inside thesubtank unit 33. Therefore, the elastic wave generating device 3 canaccurately detect the ink surface when the ink surface inside thesubtank unit 33 reaches to the lower end of the porous member 1050 andexits between the ink layer 1060. Moreover, the elastic wave generatingdevice 3 can detect the ink quantity and existence of ink inside thesubtank unit 33 accurately.

[0490] Moreover, because the elastic wave generating device 3 isprovided inside the subtank unit 33, the elastic wave generating device3 can detect the ink quantity and the existence of ink inside thesubtank unit 33 even when the ink inside the ink cartridge 180 is usedup. Therefore, the ink jet recording apparatus can judge whether theprinting process can be continued or not.

[0491] The elastic wave generating device 3 and the porous member 1050are provided inside the container 1 of the ink cartridge in theembodiment shown in FIG. 91. Moreover, as shown in FIGS. 91 and 92, theelastic wave generating device 3 and the porous member 1050 are alsoprovided inside the subtank unit 33. Therefore, the elastic wavegenerating device 3 and the porous member 1050 are provided on both ofthe ink cartridge shown in FIG. 91 and the subtank unit 33 shown in FIG.92. However, the elastic wave generating device 3 and the porous member1050 can be provided to only one of the ink cartridge shown in FIG. 91or the subtank unit 33 shown in FIG. 92.

[0492] According to the embodiment shown in FIG. 93, if the inkabsorbing member 74 and 75 expose from the ink by consumption of inkinside the container 1, ink contained in the ink absorbing member 74 and75, which is made from a porous material, flows out by the own weightand is supplied to the recording head 31. If ink is used up, the inkabsorbing member 74 and 75 absorbs the ink remained in the through hole1 c, the ink is thereby drained from the concave part of the throughhole 1 c. Therefore, the condition of the reflective wave of the elasticwave generated by the elastic wave generating device 70 at the ink endstatus changes, and thus the timing of ink end status can be furtheraccurately detected. Furthermore, the ink absorbing member 74 and 75 aredesigned such that the capillary force works in the ink absorbing member74 and 75 is equal to the capillary force which can hold ink or greaterthan the capillary force which can hold ink. The ink absorbing member 74and 75 thereby absorb ink remained in the through hole 1 c.

[0493] FIGS. 94(I)-94(V) show manufacturing methods of the elastic wavegenerating device 3, 15, 16 and 17. A base plate 20 is formed bymaterial such as the burning-endurable ceramic. Referring to FIG. 94(I),first of all, a conductive material layer 21 which becomes an electrodeat one side is formed on the base plate 20. Next, referring to FIG.94(II), a green sheet 22 serving as piezoelectric material is placed onthe conductive material layer 21. Next, referring to FIG. 94(III), thegreen sheet 22 is formed in a predetermined shape by a press processingor the like and is made into the form of a vibrator, and is air-dried.Thereafter, the burning is performed on the green sheet 22 at a burningtemperature of, for example, 1200° C. Next, referring to FIG. 94(IV) , aconductive material layer 23 serving as other electrode is formed on thesurface of the green sheet 22 so as to be polarized in a capable offlexural-oscillation manner. Finally, referring to FIG. 94(V), the baseplate 20 is cut along each element. By fixing the base plate 20 in apredetermined face of the container 1 by use of adhesive or the like,the elastic wave generating device 3 can be fixed on the predeterminedface of the container and the ink cartridge is completed which has abuilt-in function which detects the ink remaining amount.

[0494]FIG. 95 shows another embodiment of the elastic wave generatingdevice 3 shown in FIG. 94. In the embodiment shown in FIG. 94, theconductive material layer 21 is used as a connecting electrode. On theother hand, in the embodiment shown in FIG. 95, connecting terminals 21a and 23 a are formed by a solder in an upper position than the surfaceof the piezoelectric material layer comprised of the green sheet 22. Bythe provision of the connecting terminals 21 a and 23 a, the elasticwave generating device 3 can be directly mounted to the circuit board,so that inefficient connection such as one by lead wires can be avoided.

[0495] Now, the elastic wave is a type of waves which can propagatethrough gas, liquid and solid as medium. Thus, the wavelength,amplitude, phase, frequency, propagating direction and propagatingvelocity of the elastic wave change based on the change of medium inquestion. On the other hand, the state and characteristic of thereflected wave of the elastic wave change according to the change of themedium. Thus, by utilizing the reflected wave which changes based on thechange of the medium through which the elastic wave propagates, thestate of the medium can be observed. In a case where the state of theliquid inside the liquid container is to be detected by this method, anelastic wave transmitter-receiver will be used for example. Let usexplain this by referring to embodiments shown in FIGS. 90-91. First,the transmitter-receiver gives out the elastic wave to the medium, forexample, the liquid or the liquid container. Then, the elastic wavepropagates through the medium and arrives at the surface of the liquid.Since a boundary is formed between the liquid and the gas on the liquidsurface, the reflected wave is returned to the transmitter-receiver. Thetransmitter-receiver receives the reflected wave. A distance between theliquid surface and a transmitter or receiver can be measured based on anoverall traveled time of the reflected wave, or a damping factor of theamplitudes of the elastic wave generated by the transmitter and thereflected wave reflected on the liquid surface, and soon. Utilizingthese, the state of the liquid inside the liquid container can bedetected. The elastic wave generating device 3 may be used as a singleunit of the transmitter-receiver in the method utilizing the reflectedwave based on the change of the medium through which the elastic wavepropagates, or a separately provided receiver may be mounted thereto.

[0496] As described above, in the elastic wave, generated by the elasticwave generating device 3, propagating through the ink liquid, thetraveling time of the reflected wave occurring on the ink liquid surfaceto arrive at the elastic wave generating device 3 varies depending ondensity of the ink liquid and the liquid level. Thus, if the compositionof ink is fixed, the traveling time of the reflected wave which occurredin the ink liquid surface varies depending on the ink amount. Therefore,the ink amount can be detected by detecting the time period during whichthe elastic wave generating device 3 generates the elastic wave and thenthe wave reflected from the ink surface arrives at the elastic wavegenerating device 3. Moreover, the elastic wave vibrates particlescontained in the ink. Thus, in a case of using pigment-like ink whichuses pigment as a coloring agent, the elastic wave contributes toprevent precipitation of the pigment or the like.

[0497] By providing the elastic wave generating device 3 in thecontainer 1, when the ink of the ink cartridge approaches (decreases to)an ink-end state and the elastic wave generating device 3 can no longerreceive the reflected wave, it is judged as an ink-near-end and thus cangive indication to replace the cartridge.

[0498]FIG. 96 shows an ink cartridge according to another embodiment ofthe present invention. Plural elastic wave generating device 41-44 areprovided on the side wall of the container 1, spaced at a variableinterval from one another in the vertical direction. In the inkcartridge shown in FIG. 96, whether or not the ink is present atmounting levels of respective elastic wave generating device 41-44 canbe detected by whether or not the ink is present at respective positionsof the elastic wave generating device 41-44. For example, suppose thatthe liquid level of ink is at a point between the elastic wavegenerating device 44 and 43. Then, the elastic wave generating device 44detects and judges that the ink is empty while the elastic wavegenerating device 41, 42 and 43 detect and judge respectively that theink is present. Thus, it can be known that the liquid level of ink liesin a level between the elastic wave generating device 44 and 43. Thus,provision of the plural elastic wave generating device 41-44 makespossible to detect the ink remaining amount in a step-by-step manner.

[0499]FIGS. 97 and 98 show ink cartridges according to still anotherembodiments of the present invention. In an embodiment shown in FIG. 97,an elastic wave generating device 65 is mounted in a bottom face 1 aformed aslope in the vertical direction. In an embodiment shown in FIG.98, an elastic wave generating device 66 of an elongated shape in thevertical direction is provided in the vicinity of the bottom face of aside wall 1 b.

[0500] According to the embodiments shown in FIGS. 97 and 98, when partof the elastic wave generating device 65 and 66 is exposed from theliquid surface, the traveled time of the reflected wave and the acousticimpedance of the elastic waves generated by the elastic wave generatingdevice 65 continuously change corresponding to the change (Δh1, Δh2) ofthe liquid surface. Thus, the process from the ink-near-end state to theink-end state of ink remaining amount can be accurately detected bydetecting the degree of change in the traveled time of the reflectedwave or the acoustic impedance of the elastic waves.

[0501] Furthermore, a porous member 1050 is provided inside thecontainer 1. The porous member 1050 prevents the waving and bubbling ofink inside the container 1. The porous member 1050 thereby prevents theelastic wave generating device 65 and 66 to detects the ink existencemistakenly.

[0502] In the embodiment shown in FIG. 97, the porous member 1050 isprovided in the container 1 such that the slope of the bottom face 1055of the porous member 1050 is parallel to the slope of the elastic wavegenerating device 65. A gap is provided between the bottom face 1055 andthe elastic wave generating device 65 and forms a ink layer 1060.Therefore, as the embodiment shown in FIG. 90, when the ink surface inthe container 1 reaches to the lower end of the porous member 1050 andexists within the ink layer 1060, the elastic wave generating device 3can detect the ink surface accurately.

[0503] In the embodiment shown in FIG. 98, one side face of the porousmember, not shown in the figure, is provided in the container 1 suchthat the one side face is parallel to the elastic wave generating device66. A gap is provided between the one side face and the side wall 1 a.In the present embodiment, when ink is filled inside the container 1 andgap between the one side face of the porous member and the side wall 1b, the reflective wave of the elastic wave generated by the elastic wavegenerating device 66 does not change. On the other hand, if ink insidethe container 1 is consumed, and the gap between the one side face ofthe porous member and the side wall 1 b arises, the reflective wave ofthe elastic wave generated by the elastic wave generating device 66gradually changes. Therefore, the elastic wave generating device 66 candetect the ink consumption status when the ink surface exists within theregion of the length Δh2 of the elastic wave generating device 66. Thelength of the elastic wave generating device 66 is not limited.

[0504] Though in the above embodiments a flexural oscillating typepiezoelectric vibrator is used so as to suppress the increase of thecartridge size, a vertically vibrating type piezoelectric vibrator mayalso be used. In the above embodiments, the elastic wave is transmittedand received by a same elastic wave generating device. In still anotherembodiment, the elastic wave generating device may be providedseparately as one for use in transmitting the elastic wave and other forreceiving the elastic wave, so as to detect the ink remaining amount.

[0505]FIG. 99 shows an ink cartridge according to still anotherembodiment of the present invention. Plural elastic wave generatingdevice 65 a, 65 b and 65 c on the bottom face 1 a formed aslope in thevertical direction spaced at an interval are provided in the container1.

[0506] Furthermore, a porous member 1050 is provided inside thecontainer 1. A gap is provided between the porous member 1050 and theelastic wave generating device 65 a, 65 b, and 65 c to form an ink layer1060. By providing the porous member 1050 inside the container 1, theporous member 1050 prevents the waving or bubbling of ink inside thecontainer 1 when the ink cartridge moves together with the recordinghead by the scanning operation during the printing process. Therefore,the bubble of ink is difficult to generate around the elastic wavegenerating device 65 z, 65 b, and 65 c. Furthermore, even if the bubbleof ink generates, because the porous member 1050 absorbs the bubble ofink, the bubble does not stay around the elastic wave generating device65 a, 65 b, and 65 c. The elastic wave generating device 65 a, 65 b, and65 c can thereby accurately detect the ink consumption status.

[0507] The width of the ink layer 1060 is not limited as the embodimentt shown in FIG. 97.

[0508] According to the present embodiment, the arrival time (traveledtime) of the reflected waves of the elastic waves to the respectiveelastic wave generating device 65 a, 65 b and 65 c in the respectivemounting positions of the elastic wave generating device 65 a, 65 b and65 c differs depending on whether or not the ink is present in therespective positions of the plural elastic wave generating device 65 a,65 b and 65 c. Thus, whether or not the ink is present in the respectivemounted position levels of the elastic wave generating device 65 a, 65 band 65 c can be detected by scanning each elastic generating means (65a, 65 b and 65 c) and by detecting the traveled time of the reflectedwave of the elastic wave in the elastic wave generating device 65 a, 65b and 65 c. Hence, the ink remaining amount can be detected in astep-by-step manner. For example, suppose that the liquid level of inkis at a point between the elastic wave generating device 65 b and 65 c.Then, the elastic wave generating device 65 c detects and judges thatthe ink is empty while the elastic wave generating device 65 a and 65 bdetect and judge respectively that the ink is present. By overallevaluating these results, it becomes known that the liquid level of inklies in a level between the elastic wave generating device 65 b and 65c.

[0509]FIGS. 100 and 101 show cross sections of the ink-jet recordingapparatus according to still another embodiment of the presentinvention.

[0510]FIG. 100 shows a cross section of the ink-jet recording apparatusalone.

[0511]FIG. 101 is a cross section of the ink-jet recording apparatus towhich the ink cartridge 272 is mounted. A carriage 250 capable ofreciprocating in the direction of the width of the ink-jet recordingpaper includes a recording head 252 in a lower face thereof. Thecarriage 250 includes a subtank unit 256 in an upper face of therecording head 252. The subtank unit 256 has a similar structure to thatshown in FIG. 92. The subtank unit 256 has an ink supply needle 254facing an ink cartridge 272 mounting side. In the carriage 250, there isprovided a convex part 258 in a manner such that the convex part 258 isdisposed counter to a bottom portion of the ink cartridge 272 and in anarea where the ink cartridge 272 is to be mounted there above. Theconvex part 258 includes an elastic wave generating device 260 such asthe piezoelectric vibrator.

[0512] FIGS. 102 show an embodiment of the ink cartridge suitable forthe recording apparatus shown in FIGS. 100.

[0513]FIG. 102 shows an embodiment of the ink cartridge for use with asingle color, for instance, the black color. The ink cartridge 272according to the present embodiment, comprises a container which housesink and an ink supply port 276 which comes in contact with an ink supplyneedle 254 of the recording apparatus in a sealed manner. In thecontainer 274, there is provided the concave part 278, positioned in abottom face 274 a, which is to be engaged with the convex part 258 shownin FIG. 101. The concave part 278 houses ultrasound transferringmaterial such as gelated material 280.

[0514] The ink supply port 276 includes a packing ring 282, a valve body286 and a spring 284. The packing ring 282 is engaged with the inksupply needle 254 in a fluid-tight manner. The valve body 286 isconstantly and elastically contacted against the packing ring 282 by wayof the spring 284. When the ink supply needle 254 is inserted to the inksupply port 276, the valve body 286 is pressed by the ink supply needle254 so as to open an ink passage. On an upper wall of the container 274,there is mounted a semiconductor memory means 288 which stores data onink inside the ink cartridge and so on.

[0515] A porous member 1050 is provided inside the container 274. A gapis provided between the porous member 1050 and the gelated material 280to form an ink layer 1060. By providing the porous member 1050 insidethe container 274, the porous member 1050 prevents the waving orbubbling of ink inside the container 274. Therefore, the elastic wavegenerating device 260 can accurately detect the ink consumption statusas shown in FIG. 90.

[0516] As in the embodiment shown in FIG. 90, the present embodiment ofthe elastic wave generating device 260 can accurately detect the inksurface when the ink surface inside the container 274 reaches to thelower end of the porous member 1050 and exists within the ink layer1060. The width of the gap between the porous member 1050 and theelastic wave generating device 260 is not limited. Preferably, theporous member 1050 is provided vicinity of the elastic wave generatingdevice 260.

[0517] Referring to FIG. 101, when the ink supply port 276 of the inkcartridge 272 is inserted through the ink supply needle 254 of thesubtank unit 256, the valve body 286 recedes against the spring 284, sothat an ink passage is formed and the ink inside the ink cartridge 272flows into the ink chamber 262. At a stage where the ink chamber 262 isfilled with ink, a negative pressure is applied to a nozzle opening ofthe recording head 252 so as to fill the recording head with ink.Thereafter, the recording operation is performed. When the ink isconsumed in the recording head 252 by the recording operation, apressure in the downstream of a flexible valve 266 decreases. Then, theflexible valve 266 is positioned away from a valve body 270 so as tobecome opened. When the flexible valve 36 is opened, the ink in the inkchamber 262 flows into the recording head 252 through the ink passage35. Accompanied by the ink which has flowed into the recording head 252,the ink in the ink cartridge 272 flows into the subtank unit 256.

[0518] While the recording apparatus is operating, a drive signal issupplied to the elastic wave generating device 260 at a detection timingwhich is set in advance, for example, at a certain period of time. Theelastic wave generated by the elastic wave generating device 260 isradiated from the convex part 258 and is transferred to the ink insidethe ink cartridge 272 by propagating through the gelated material 280 inthe bottom face 274 a of the ink cartridge 272. Though the elastic wavegenerating device 260 is provided in the carriage 250 in FIGS. 101, theelastic wave generating device 260 may be provided inside the subtankunit 256.

[0519] Since the elastic wave generated by the elastic wave generatingdevice 260 propagates through the ink liquid, the traveling time of thereflected wave occurring on the ink liquid surface to arrive at theelastic wave generating device 260 varies depending on density of theink liquid and the liquid level. Thus, if the composition of ink isfixed, the traveling time of the reflected wave which occurred in theink liquid surface varies depending on the ink amount. Therefore, theink amount can be detected by detecting the time duration during whichthe reflected wave arrives at the elastic wave generating device 260from the ink liquid surface when the ink liquid surface is excited bythe elastic wave generating device 260. Moreover, the elastic wavegenerated by the elastic wave generating device 260 vibrates particlescontained in the ink. Thus, in a case of using pigment-like ink whichuses pigment as a coloring agent, the elastic wave contributes toprevent precipitation of the pigment or the like.

[0520] After the printing operation and maintenance operation or thelike and when the ink of the ink cartridge approaches (decreases to) anink-end state and the elastic wave generating device 260 can no longerreceive the reflected wave even after the elastic wave generating devicesends out the elastic wave, it is judged that the ink is in anink-near-end state and thus this judgment can give indication to replacethe cartridge anew. Moreover, when the ink cartridge 272 is not mountedproperly to the carriage 250, the shape of the elastic wave from theelastic generating means 260 changes in an extreme manner. Utilizingthis, warning can be given to a user in the event that the extremechange in the elastic wave is detected, so as to prompt the user tocheck on the ink cartridge 272.

[0521] The traveling time of the reflected wave of the elastic wavegenerated by the elastic wave generating device 260 is affected by thedensity of ink housed in the container 274. Since the density of ink maydiffer by the type of ink used, data on the types of ink are stored in asemiconductor memory means 288, so that a detection sequence can be setbased on the data and thus the ink remaining amount can be furtherprecisely detected.

[0522]FIG. 103 shows an ink cartridge 272 according to still anotherembodiment of the present invention. In the ink cartridge 272 shown inFIG. 103, the bottom face 274 a is formed aslope in the verticaldirection.

[0523] In the ink cartridge 272 shown in FIG. 103, when the inkremaining amount is becoming low and part of a radiating area of theelastic wave generating device 260 is exposed from the liquid surface,the traveled time of the reflected wave of the elastic waves generatedby the elastic wave generating device 260 continuously changescorresponding to the change Δh1 of the liquid surface. The Δh1 denoteschange of the height of the bottom face 274 a in both ends of thegelated material 280. Thus, the process from the ink-near-end state tothe ink-end state of ink remaining amount can be accurately detected bydetecting the degree of change in the traveled time of the reflectedwave of the elastic wave generating device 260.

[0524] Furthermore, a porous member 1050 is provided inside thecontainer 274. The porous member 1050 prevents the waving or bubbling ofink inside the container 274. Therefore, the elastic wave generatingdevice 260 can accurately detect the ink consumption status.

[0525] The porous member 1050 is provided in the container 274 such thatthe slope of the bottom face 1055 of the porous member 1050 is parallelto the slope of the bottom face of the container 274. A gap is providedbetween the bottom face 1055 and the elastic wave generating device 260and forms a ink layer 1060.

[0526] When ink is filled inside the container 274 and ink layer 1060,the reflective wave of the elastic wave generated by the elastic wavegenerating device 260 does not change. On the other hand, if ink insidethe container 274 is consumed, gap arises in the ink layer 1060 insteadof ink. With the arising of the gap in the ink layer 1060, thereflective wave of the elastic wave generated by the elastic wavegenerating device 260 gradually changes. Therefore, the elastic wavegenerating device 260 can detect the ink quantity when the ink status inthe container 274 is near to ink end status. The width of the ink layer1060 is not limited as the embodiment shown in FIG. 97.

[0527]FIG. 104 shows an ink cartridge 272 and an ink-jet recordingapparatus according to still another embodiment of the presentinvention. The ink-jet recording apparatus shown in FIG. 104 includes aconvex part 258′ in a side face 274 b in an ink supply port 276 side ofthe ink cartridge 272. The convex part 258′ includes an elastic wavegenerating device 260′. Gelated material 280′ is provided in the sideface 274 b of the ink cartridge 272 so as to engage with the convex part258′. According to the ink cartridge 272 shown in FIG. 104, when the inkremaining amount is becoming low and part of a radiating area of theelastic wave generating device 260′ is exposed from the liquid surface,the traveled time of the reflected wave of the elastic waves generatedby the elastic wave generating device 260′ and the acoustic impedancecontinuously change corresponding to the change Δh2 of the liquidsurface. The Δh2 denotes difference in the height of both ends of thegelated material 280′. Thus, the process from the ink-near-end state tothe ink-end state of ink remaining amount can be accurately detected bydetecting the degree of change in the traveled time of the reflectedwave of the elastic wave generating device 260 or change in the acousticimpedance.

[0528] The ink cartridge according to the present embodiment further hasa porous member 1050 provided inside the container 274. The ink-jetrecording apparatus includes a convex part 258′ in a side face 274 b inan ink supply port 276 side of the ink cartridge 272. The convex part258′ includes an elastic wave generating device 260′. The side face 1056of the porous member 1050 is parallel to the side face 274 b of thecontainer 274. An ink layer 1060 is formed on the gap between the sideface 1056 and the elastic wave generating device 260′.

[0529] The porous member 1050 prevents the waving or bubbling of inkinside the container 274. Therefore, the elastic wave generating device260′ can accurately detect the ink consumption status.

[0530] When ink is filled inside the container 274 and ink layer 1060,the reflective wave of the elastic wave generated by the elastic wavegenerating device 260′ does not change. On the other hand, if ink insidethe container 274 is consumed, gap arises in the part corresponding tothe Δh2 which is a width in the height direction of the gelated material280′ within the ink layer 1060. With the arising of the gap in the inklayer 1060, the reflective wave of the elastic wave generated by theelastic wave generating device 260′ gradually changes. Therefore, theelastic wave generating device 260′ can detect the ink consumptionstatus when the is ink surface within the width Δh2 in the heightdirection.

[0531] If the ink surface is within the region of the Δh2, the elasticwave generating device 260′ can detect the ink surface. According to theink cartridge according to the present embodiment, there is a gapbetween the side face 1056 of the porous member 1050 and the elasticwave generating device 260′, the elastic wave generating device 260′ candetect the ink surface within the region of the Δh2 even if the porousmember 1050 is provided in the container 274. Therefore, by widen thewidth of the Δh2, the elastic wave generating device 260′ can detect theink surface when ink is filled in the container 274 until the inksurface when ink in the container 274 is nearly end.

[0532] In the above embodiments, the elastic wave is transmitted andreceived by the same elastic wave generating device 260 and 260′ whenthe ink remaining amount is detected based on the reflected wave at theliquid surface. The present invention is not limited thereby and forexample, as still another embodiment the elastic wave generating device260 may be provided separately as one for use in transmitting theelastic wave and other for receiving the elastic wave, so as to detectthe ink remaining amount.

[0533]FIG. 105 is a cross sectional view of an embodiment of an inkcartridge for use with a single color, for example, the black ink. Theink cartridge shown in FIG. 105 has a actuator 106. An ink supply port 2which comes in contact with an ink supply needle of the recordingapparatus in a sealed manner is provided in a container 1 which housesthe ink. In an outside portion of a bottom face 1 a of the container 1,the actuator 106 is mounted such that the actuator 106 can contact withink inside the container 1 via the through hole 1 c provided in thecontainer 1. In order that at a stage at which the ink K is almost usedup, i.e. at the time when the ink becomes an ink-end state, the statusaround the actuator 106 can change from the liquid to the gas, theactuator 106 is provided in a slightly upward position from the inksupply port 2. Moreover, an actuator 106 may be separately providedinstead, so that the actuator 106 is used as an means for detectingliquid only.

[0534] Furthermore, a porous member 1050 is provided inside thecontainer 1. The porous member 1050 is provided around the actuator 106inside the container 1. A gap having a same depth with the through hole1 c is provided between the porous member 1050 and the actuator 106. Byproviding the porous member 1050 inside the container 1, the porousmember 1050 prevents the waving or bubbling of ink inside the container1 when the ink cartridge moves together with the recording head by thescanning operation during the printing process. Therefore, the bubble ofink is difficult to generate around the actuator 106. The actuator 106can thereby detect the ink consumption status accurately.

[0535] Moreover, the width of the gap between the porous member 1050 andthe actuator 106 is not limited. To suppress the bubbling of ink as muchas possible, the width of ink layer 1060 is reduced by providing theporous member 1050 on lower side of the container 1. If the width of theink layer 1060 is small, the actuator 106 can detect the ink quantityonly when the ink status is near to the ink end. However, ink does notwave inside the container 1. Therefore, the actuator 106 can accuratelydetect the ink quantity when the ink consumption status is near to theink end status. Therefore, the porous member 1050 is preferably locatednearby the actuator 106 without limiting the width of gap between theporous member 1050 and the actuator 106.

[0536] Furthermore, the hole diameter of porous member 1050 is set suchthat the porous member 1050 does not absorbs ink existed in the throughhole 1 c before the ink surface reaches to the through hole 1 c. Inother words, the porous member 1050 is designed such that the capillaryforce works in the porous member 1050 is smaller than the capillaryforce which can hold ink in the container 1. Therefore, ink does notremain in the porous member 1050 by its own weight and exists in thethrough hole 1 c when the ink inside the container 1 is in an ink nearend status. Furthermore, an airhole, not shown in the figure, isprovided on the container 1. The airhole is provided on the upper sideof the container 1 to communicate with outside of container 1. Air isintroduced inside the container 1 by the airhole, and ink flows downwardby own weight with advance of ink consumption. The residual ink therebystays in the through hole 1 c.

[0537] On the other hand, the hold diameter of the porous member 1050can be set such that the porous member 1050 absorbs ink existed in thethrough hole 1 c when the predetermined amount of the ink is consumed.That is, the hole diameter of the porous member 1050 is set that thecapillary force works in the porous member 1050 is equal to or largerthan the capillary force which can hold ink inside the container 1. Theporous member 1050 thereby absorbs ink existed in the through hole 1 cwhen the predetermined amount of ink inside of the container 1 isconsumed. Furthermore, the hole diameter of the porous member 1050 of apart nearby the ink supply port 2 is made smaller than the hole diameterof the other part of the porous member 1050. Ink existed in the throughhole 1 c is thereby absorbed by the porous member 1050 and furthersupplied to the ink supply port 2 from the porous member 1050.

[0538] For example, the hole diameter of the porous member 1050 isdesigned such that the porous member 1050 absorbs ink remained in thethrough hole 1 c when the ink quantity in the ink cartridge becomessmall amount in a degree that printing becomes defective. Furthermore,the hole diameter of the porous member 1050 is designed such that theporous member 1050 can send the ink, which is absorbed from the throughhole 1 c by the porous member 1050, to the ink supply port 2. Theactuator 106 can thereby detects the ink end accurately when thepredetermined amount of ink is consumed and prevents the defectiveprinting. More specifically, the hole diameter of the porous member 1050nearby the actuator 106 is made larger than the hole diameter of theporous member 1050 around the ink supply port 2.

[0539] The porous member 1050 occupies more than half of the volume ofthe container 1. However, a relatively small porous member, not shown inthe figure, can be provided only around the actuator 106.

[0540]FIG. 106 is a cross sectional view of the bottom part of the inkcartridge of the present embodiment. The ink cartridge of the presentembodiment has a through hole 1 c on the bottom face 1 a of thecontainer 1, which contains ink. The bottom part of the through hole 1 cis closed by the actuator 650 and forms an ink storing part.

[0541] The ink cartridge according to the present embodiment has aporous member 1050 provided inside the through hole 1 c. The porousmember 1050 thereby contacts with the vibrating region of the actuator650. By providing the porous member 1050 to contact with the vibratingregion of the actuator 650, ink does not remained in the through hole 1c.

[0542] For example, the hole diameter of the porous member 1050 bprovided around the through hole 1 c is made smaller than the holediameter of the porous member 1050 a provided inside the through hole 1c. The capillary force of the porous member 1050 a around the throughhole 1 c thereby becomes smaller than the capillary force of the porousmember 1050 a inside of the through hole 1 c. Therefore, ink containedin the porous member 1050 a inside the through hole 1 c is absorbed bythe porous member 1050 b provided around the through hole 1 c when theink inside the ink cartridge is consumed. Thus, ink does not remain inthe through hole 1 c. Therefore, the accuracy of detecting the inkconsumption status inside the ink cartridge by the actuator 650 can beimproved.

[0543]FIG. 107 is a cross sectional view showing an embodiment of amajor part of the ink-jet recording apparatus suitable for the inkcartridge shown in FIGS. 105 and 106. A carriage 30 capable ofreciprocating in the direction of the width of the recording paper isequipped with a subtank unit 33, while the recording head 31 is providedin a lower face of the subtank unit 33. Moreover, the ink supply needle32 is provided in an ink cartridge mounting face side of the subtankunit 33.

[0544] While the recording apparatus is operating, a drive signal issupplied to the actuator 106 at a detection timing which is set inadvance, for example, at a certain period of time.

[0545] By adhering the actuator 106 to the container 1, a process ofembedding electrodes for use in detecting the liquid surface isunnecessary in the course of forming the container 1. Therefore, aninjection molding process can be simplified and the leakage of theliquid from a place in which the electrodes are supposedly embedded canbe avoided, thus improving the reliability of the ink cartridge.

[0546]FIG. 108 is a cross sectional view of another embodiment of asubtank unit 33. The subtank unit 33 shown in FIG. 108 comprises theactuator 106 and a porous member 1050. In the embodiment shown in FIG.27, the actuator 106 and the porous member 1050 are provided in thecontainer 1 of the ink cartridge. However, as shown in FIG. 108, theactuator 106 and the porous member 1050 can be provided inside thesubtank unit 33. Furthermore, the actuator 106 and the porous member1050 can be provided in both of inside the container 1 of the inkcartridge and the subtank unit 33.

[0547] According to the embodiment shown in FIG. 108, the actuator 106can detect the ink quantity and the existence of ink inside the subtankunit 33. Furthermore, the porous member 1050 can prevents the waving andbubbling of ink inside the subtank unit 33. Therefore, the actuator 106can accurately detects the ink quantity and the existence of ink.Moreover, because the actuator 106 is provided inside the subtank unit33, the actuator 106 can detect the ink quantity and the existence ofink inside the subtank unit 33 even when there is no ink inside the inkcartridge. The ink jet recording apparatus thereby can judges whetherthe printing operation can be continued or not.

[0548] If the actuator 106 and the porous member 1050 are provided onboth inside of the container 1 of the ink cartridge and the subtank unit33, the actuator 106 can detect the ink consumption status moreaccurately. Furthermore, the actuator 106 can detect the timing of inkend inside the container 1 of the ink cartridge.

[0549]FIG. 109 show ink cartridges according to still anotherembodiments of the present invention. In an embodiment shown in FIG.109, a actuator 106 is mounted in a bottom face 1 a formed aslope in thevertical direction.

[0550] According to the embodiments shown in FIG. 109, when part of theactuator 106 is exposed from the liquid surface, the residual vibrationof the actuator 106 continuously changes. Therefore, the actuator 106can accurately detect the ink consumption quantity by detecting thechange of the acoustic impedance. For example, the actuator 106 candetect the ink surface while the ink surface exists within the region ofthe Δh1 shown in FIG. 109.

[0551] In the embodiment, the porous member 1050 is provided in thecontainer 1. The porous member 1050 prevents the waving and bubbling ofink inside the container 1. The porous member 1050 thereby improves theaccuracy of detecting the ink quantity by the actuator 106.

[0552] In the embodiment shown in FIG. 109, the porous member 1050 isprovided nearby the actuator 106. However, the present embodiment doesnot provide the porous member 1050 inside the through hole 1 c.Therefore, ink directly contacts with the vibration region of theactuator 106. Thus, the vibration region of the actuator 106 exposed toair with the increase in consumption of ink. Then, the vibration statusat the vibration region of the actuator 106 changes. Therefore, todetect the ink quantity by the actuator 106 becomes easy.

[0553] To suppress the waving and bubbling of ink as much as possible,it is not preferable to have a gap between the porous member 1050 andthe actuator 106. On the other hand, it is also not preferable that theporous member 1050 adhere to the vibrating region of the actuator 106 ina degree that the vibrating section of the actuator 106 cannot vibrate.Therefore, the porous member 1050 is preferable to provided around thevibrating region of the actuator 106. However, the porous member 1050can be contacts with the vibrating region of the actuator 106 if thevibrating region of the actuator 106 can vibrate and detect the inkexistence and the ink quantity.

[0554]FIG. 110 shows an ink cartridge according to still anotherembodiment of the present invention. Plural actuators 106 a, 106 b, and106 c on the bottom face 1 a formed a slope in the vertical directionspaced at an interval are provided in the container 1. Furthermore, aporous member 1050 is provided inside the container 1. The porous member1050 prevents the actuators 106 a, 106 b, and 106 c to wrongly detectthe ink consumption status as explained in the FIG. 109.

[0555] According to the present embodiment, depends on whether the inkis existed in the mounting position of each of the actuators 106 a, 106b, and 106 c, the amplitude of the residual vibration and a resonantfrequency of the each of the actuators 106 a, 106 b, and 106 c differsat each of the mounting position of the actuators 106 a, 106 b, and 106c. Therefore, the existence of ink at the level of the mounting positionof each of the actuators 106 a, 106 b, and 106 c can be detected bymeasuring the counter electromotive force of the residual vibration ofeach of the actuators 106 a, 106 b, and 106 c. Therefore, residualquantity of ink can be detected step by step. For example, if the inksurface is at the level between the actuator 106 b and the actuator 106c, the actuator 106 a detects non-ink status, and the other actuators106 b and 106 c detects ink-exist status. By comprehensively judgingthese detecting results, it can be known that the ink surface positionsbetween the mounting position of the actuator 106 b and actuator 106 c.

[0556]FIG. 111 shows other embodiment of the through hole 1 c. In eachof FIG. 111(A), (B), and (C), the left hand side of the figure shows thestatus that there is no ink K in the through hole 1 c, and the righthand side of the figure shows the status that ink K is remained in thethrough hole 1 c. In the embodiment of FIG. 28, the side face of thethrough hole 1 c is formed as the vertical wall. In FIG. 111(A), theside face 1 d of the through hole 1 c is slanted in vertical directionand opens with expanding to the outside. In FIG. 111(B), a steppedportion 1 e and 1 f are formed on the side face of the through hole 1 c.The stepped portion 1 f, which is provided above the stepped portion 1e, is wider than the stepped portion 1 e. In FIG. 111(C), the throughhole 1 c has a groove 1 g that extends to the direction in which ink iseasily discharged, that is, the direction to a ink supply port 2.

[0557] According to the shape of the through hole 1 c shown in FIG.111(A) to (C), the quantity of ink K in the ink storing part can bereduced. Therefore, because the M′cav can be smaller than the M′maxexplained in FIGS. 22 and 23, the vibration characteristic of theactuator 650 at the time of the ink end status can be greatly differentwith the vibration characteristic when enough quantity of ink K forprinting is remained in the container 1, and thus the ink end status canbe reliably detected.

[0558] Furthermore, in the ink cartridge of the present embodiment, aporous member, not shown in FIG. 111, is provided around the throughhole 1 c of the FIGS. 111(A), 111(B), and 111(C). The porous member 1050becomes easy to absorb ink inside the through hole 1 c by forming theside face 1 d, stepped portion 1 e, and 1 f, or groove 1 g.

[0559]FIG. 112 is a slant view of the further other embodiment of theactuator. In this embodiment, the actuator 670 comprises a concave partforming base plate 80 and a piezoelectric element 82. The concave part81 is formed on the one side of the face of the concave part formingbase plate 80 by the technique such as etching, and piezoelectricelement 82 is mounted on the other side of the face of the concave partforming base plate 80. The bottom portion of the concave part 81operates as a vibrating region within the concave part forming baseplate 80. Therefore, the vibrating region of the actuator 670 isdetermined by the periphery of the concave part 81. Furthermore, theactuator 670 has the similar structure with the structure of theactuator 106 shown in FIG. 22, in which the base plate 178 and thevibrating plate 176 is formed as one body. Therefore, the manufacturingprocess during the manufacturing an ink cartridge can be reduced, andthe cost for manufacturing an ink cartridge also can be reduced. Theactuator 670 has a size which can be embedded into the through hole 1 cprovided on the container 1. By this embedding process, the concave part81 can operates as the cavity. The actuator 106 shown in FIG. 22 can beformed to be embedded into through hole 1 c as actuator 670 shown inFIG. 112. Furthermore, a porous member 1050 is provided around theactuator 670.

[0560] The actuator 106 of the ink cartridge 180B shown in FIG. 113 ismounted on the side wall of the supply port of the ink container 194.The actuator 106 can be mounted on the side wall or bottom face of theink container 194 if the actuator 106 is mounted nearby the ink supplyport 187. The actuator 106 is preferably mounted on the center of thewidth direction of the ink container 194. Because ink is supplied to theoutside through the ink supply port 187, ink and actuator 106 reliablycontacts until the timing of the ink near end by providing the actuator106 nearby the ink supply port 187. Therefore, the actuator 106 canreliably detect the timing of the ink near end. A porous member 1050 isprovided around the actuator 106. The porous member 1050 prevents thewaving and the bubbling of ink and thereby prevents the actuator 106 towrongly detect the ink consumption status.

[0561] Furthermore, by providing the actuator 106 nearby the ink supplyport 187, the setting position of the actuator 106 to the connectionpoint on the carriage on the ink container becomes reliable during themounting of the ink container on the cartridge holder of the carriage.It is because the reliability of coupling between the ink supply portwith the ink supply needle is most important during the coupling of theink container and the carriage. If there is even a small gap, the tip ofthe ink supply needle will be hurt or a sealing structure such as O-ringwill be damaged so that the ink will be leaked. To prevent this kind ofproblems, the ink jet printer usually has a special structure that canaccurately positioning the ink container during the mounting of the inkcontainer on the carriage. Therefore, the positioning of the actuator106 becomes reliable by arranging the actuator nearby the ink supplyport. Furthermore, the actuator 106 can be further reliably positionedby mounting the actuator 106 at the center of the width direction of theink container 194. It is because the rolling is the smallest when theink container rolls along an axis, the center of which is center line ofthe width direction, during the mounting of the ink container on theholder.

[0562]FIG. 114 shows further other embodiment of the ink cartridge 180.FIG. 114 shows a cross section of an ink cartridge 180C. Thesemiconductor memory device 7 and the actuator 106 are formed on thesame circuit board 610 in the ink cartridge 180C.

[0563]FIG. 115 shows further other embodiment of the ink cartridge 180.A plurality of actuators 106 is mounted on the side wall 194 b of theink container 194 in the ink cartridge 180D shown in FIG. 115. It ispreferable to use the plurality of the actuators 106 which is formed inone body as shown in FIG. 26 for these plurality of actuators 106. Theplurality of actuators 106 is arranged on the side wall 194 b withinterval in vertical direction. By arranging the plurality of actuators106 on the side wall 194 b with interval in vertical direction, theresidual quantity of ink can be detected step by step.

[0564] The ink cartridge 180E shown in FIG. 115 mounts a actuator 606which is long in vertical direction on the side wall 194 b of the inkcontainer 194. The change of the residual quantity of ink inside the inkcontainer 194 can be detected continuously by the actuator 606 which islong in vertical direction. The length of the actuator 606 is preferablylonger than the half of the height of the side wall 194 b. In FIG. 115,the actuator 606 has the length from the substantially from the top endto the bottom end of the side wall 194 b.

[0565] The ink cartridge 180F shown in FIG. 115 mounts a plurality ofactuators 106 on the side wall 194 b of the ink container 194 as the inkcartridge 180D shown in FIG. 115. The ink cartridge 180F furthercomprises the wave preventing wall 192, which is long in verticaldirection, along the side wall 194 b with predetermined space with theside wall 194 b such that the wave preventing wall 192 faces directly tothe plurality of actuators 106. It is preferable to use the plurality ofthe actuators 106 which is formed in one body as shown in FIG. 26 forthese plurality of actuators 106. A gap which is filled with ink isformed between the actuator 106 and the wave preventing wall 192.Moreover, the gap between the wave preventing wall 192 and the actuator106 has a space such that the gap does not hold ink by capillary force.When the ink container 194 is rolled, ink wave is generated inside theink container 194 by the rolling, and there is possibility that theactuator 106 malfunctions by detecting gas or an air bubble caused bythe shock of the ink wave. By providing the wave preventing wall 192,ink wave around the actuator 106 can be prevented so that themalfunction of the actuator 106 can be prevented. The wave preventingwall 192 also prevents the air bubble generated by the rolling of ink toenter to the actuator 106.

[0566] Furthermore, a porous member 1050 is provided around the actuator106 in the embodiments shown in FIGS. 115(A), 115(B), and 115(C). Theporous member 1050 prevents the waving or bubbling of ink and preventsthe actuator 106 to wrongly detect the ink consumption status.

[0567] The embodiment that the actuator 106 is mounted on an inkcartridge or a carriage, in which the ink cartridge is a separate bodywith the carriage and mounted on the carriage, has been explained above.However, the actuator 106 can be mounted on the ink tank which ismounted on the ink jet recording apparatus together with a carriage andformed together with a carriage as one body. Furthermore, the actuator106 can be mounted on the ink tank of the off-carriage type. Theoff-carriage type ink tank is a separate body with a carriage andsupplies ink to carriage through such as tube. Moreover, the actuator ofthe present embodiment can be mounted on the ink cartridge constitutedso that a recording head and an ink container are formed as on body andpossible to be exchanged.

[0568] Although the present invention has been described by way ofexemplary embodiments, it should be understood that many changes andsubstitutions may be made by those skilled in the art without departingfrom the spirit and the scope of the present invention which is definedonly by the appended claims.

[0569] The liquid container according to the present invention canreliably detect a liquid consumption status and dispense with acomplicated sealing structure.

[0570] The liquid container according to the present invention canprevent the waving or bubbling of liquid around the piezoelectricdevice.

[0571] Furthermore, the liquid container according to the presentinvention has a piezoelectric device which can reliably detect a liquidconsumption status by detecting the liquid surface even in the case thatliquid inside the liquid container waves and bubbles.

[0572] Furthermore, the liquid container according to the presentinvention can reliably detect a liquid consumption status in the liquidcontainer even if the piezoelectric device is mounted on the upper sideof the liquid surface in the liquid container.

[0573] Furthermore, the liquid container according to the presentinvention can reliably detect a liquid consumption status in the liquidcontainer even if the piezoelectric device is mounted on the top wallwhich is located above the liquid surface in the liquid container.Therefore, the degree of freedom to design the mounting position of thepiezoelectric device can be increased.

[0574] Furthermore, the liquid container according to the presentinvention can reliably detect a liquid consumption status in the liquidcontainer by reducing the amount of liquid remained inside of a cavityafter the consumption of the liquid inside the liquid container.

What is claimed is:
 1. A liquid container, comprising: a housingcontaining therein liquid; a liquid supply opening formed in saidhousing for withdrawing the liquid from said housing; a liquid sensormounted on said housing for detecting a level of the liquid which isvariable in accordance with a consumption of the liquid; and a firstpartition wall extending in an interior of said housing and defining theinterior of said housing into at least two liquid accommodating chamberswhich communicate with each other, said liquid accommodating chamberscomprising: an air-communication side liquid accommodating chamber whichcommunicates with ambient air; and a detection side liquid accommodatingchamber in which said liquid sensor is disposed at an upper portionthereof.
 2. The liquid container according to claim 1, furthercomprising a porous member accommodated within said detection sideliquid accommodating chamber.
 3. The liquid container according to claim1, wherein said liquid supply opening is formed in saidair-communication side liquid accommodating chamber.
 4. The liquidcontainer according to claim 1, wherein said liquid supply opening isformed in said detection side liquid accommodating chamber.
 5. Theliquid container according to claim 1, further comprising a porousmember accommodated within said air-communication side liquidaccommodating chamber.
 6. The liquid container according to claim 1,wherein a volume of said air-communication side liquid accommodatingchamber is different from that of said detection side liquidaccommodating chamber.
 7. The liquid container according to claim 6,wherein the volumes of said at least two liquid accommodating chambersdecreases from one side wall of said housing to the other opposite wall.8. The liquid container according to claim 1, further comprising asecond partition wall extending in said detection side liquidaccommodating chamber and defining at least two small detectionchambers.
 9. The liquid container according to claim 8, wherein saidsecond partition wall is formed with a liquid communication opening at alower part thereof.
 10. The liquid container according to claim 8,wherein said second partition wall is formed with a liquid communicationopening at an upper part thereof.
 11. The liquid container according toclaim 8, wherein said detection sensor is disposed on each of said smalldetection chambers.
 12. The liquid container according to claim 8,wherein volumes of said small detection chambers are different from eachother.
 13. The liquid container according to claim 12, wherein thevolumes of said at least two small detection chambers decreases from oneside wall of said housing to the other opposite wall.
 14. The liquidcontainer according to claim 1, wherein said detection side liquidaccommodating chamber generates no capillary force for holding theliquid.
 15. The liquid container according to claim 8, wherein saidsmall detection chamber generates no capillary force for holding theliquid.
 16. The liquid container according to claim 1, wherein saiddetection side liquid accommodating chamber comprises a recessed partformed at a top wall thereof.
 17. The liquid container according toclaim 1, wherein said liquid sensor comprises a cavity which openstoward an interior of said housing for contacting the liquid.
 18. Theliquid container according to claim 1, wherein said liquid sensorcomprising a piezoelectric device having a vibrating section, saidvibrating section generates a counter electromotive force in accordancewith a residual vibration of said vibrating section.
 19. The liquidcontainer according to claim 1, wherein said liquid sensor detects atleast an acoustic impedance of the liquid and detects a liquidconsumption status in accordance with the acoustic impedance.
 20. Theliquid container according to claim 1, wherein the liquid container ismounted on an ink-jet printing apparatus having a printhead which ejectsink droplets, and the liquid container supplies the liquid containedtherein to the printhead through said liquid supply opening.
 21. Theliquid container according to claim 8, wherein a porous member isaccommodated within each of said at least two small detection chambers.22. The liquid container according to claim 8, wherein saidair-communication side liquid accommodating chamber includes an airholewhich communicates with ambient air, and said porous member isaccommodated within said detection side liquid accommodating chamberfarthest from said airhole among said at least two small detectionchambers.
 23. The liquid container according to claim 1, wherein saidporous member comprises a first porous material disposed closed to saidliquid sensor and a second porous material disposed far from said liquidsensor compared to said first porous material, and a pore size of saidsecond porous material is smaller than that of said first porousmaterial.
 24. The liquid container according to claim 23, wherein saidfirst porous material contacts said liquid sensor.
 25. The liquidcontainer according to claim 2, wherein a compression ratio of a portionof said porous member located far from said liquid sensor is higher thanthat of a portion of said porous member located closed to said liquidsensor.
 26. The liquid container according to claim 2, wherein saidporous member comprises a first porous material disposed close to saidliquid sensor and a second porous material disposed far from said liquidsensor compared with said first porous material, and said second porousmaterial has a higher liquid-philic characteristics than said firstporous material.
 27. A liquid container comprising: a housing containingtherein liquid; a liquid supply opening supplying liquid to an exteriorof said housing; a detection device mounted on said housing, saiddetection device comprising a piezoelectric element for detecting aliquid consumption status; and a wave absorbing wall extending in aninterior of said housing disposed at a place facing said detectiondevice.
 28. The liquid container according to claim 27, wherein a gap isdefined between said detection device and said wave absorbing wall. 29.The liquid container according to claim 28, wherein said gap does notgenerate a capillary force for holding the liquid.
 30. The liquidcontainer according to claim 28, wherein said gap generates a capillaryforce which is smaller than a force for holding the liquid.
 31. Theliquid container according to claim 27, wherein said detection devicecomprises a cavity for contacting liquid, said cavity being formed toopen toward the interior of said housing.
 32. The liquid containeraccording to claim 27, wherein said wave absorbing wall is secured toand extends from an interior wall of said housing.
 33. The liquidcontainer according to claim 27, wherein said detection device isattached to a first wall of said housing which extends in a verticaldirection of the liquid level, and said wave absorbing wall extends inparallel with said first wall of said housing.
 34. The liquid containeraccording to claim 27, wherein said detection device is attached to abottom wall of said housing, and said wave absorbing wall extends inparallel with the liquid level.
 35. The liquid container according toclaim 27, wherein said wave absorbing wall extends in an inclineddirection with respect to the liquid level.
 36. The liquid containeraccording to claim 27, wherein said wave absorbing wall extends from aside wall of said housing which is perpendicular to the liquid level.37. The liquid container according to claim 27, wherein said a capillaryforce is generated between at least a part of said wave absorbing walland an inner wall of said housing.
 38. The liquid container according toclaim 27, wherein said wave absorbing wall comprises a bending sectionwhich is formed by bending at least a part of an edge of said waveabsorbing wall toward a wall on which said detection device is mounted,and a gap defined by said bending section and said detection devicegenerates a capillary force while a gap defined by said wave absorbingwall and said detection device does not generate a capillary force. 39.The liquid container according to claim 27, wherein said wave absorbingwall comprises a plurality of wave absorbing wall pieces, and at leastone of said plurality of wave absorbing wall pieces extends from a sidewall of said housing which is perpendicular to the liquid level.
 40. Theliquid container according to claim 27, wherein said detection devicecomprises a vibrating section which generates a counter electromotiveforce in accordance with a residual vibration of said vibrating section.41. The liquid container according to claim 27, wherein the liquidcontainer is mounted on an ink-jet printing apparatus having a printheadwhich ejects ink droplets, and the liquid container supplies the liquidcontained therein to the printhead through said liquid supply opening.42. A liquid container comprising: a housing containing therein liquid;a liquid supply opening formed in a wall of said housing for withdrawingthe liquid to an exterior; a detection device mounted on said housing,said detection device comprising a piezoelectric element for detecting aliquid consumption status; and a porous member disposed within saidhousing in the vicinity of said detection device.
 43. The liquidcontainer according to claim 42, wherein said detection device contactssaid porous member.
 44. The liquid container according to claim 42,wherein a gap is defined between said porous member and said detectiondevice.
 45. The liquid container according to claim 42, wherein saiddetection device comprises a cavity and a vibrating section whichcontacts the liquid through said cavity, and said porous member isdisposed in said cavity.
 46. The liquid container according to claim 42,wherein a capillary force of said porous member is smaller than a forcewhich holds the liquid.
 47. The liquid container according to claim 42,wherein said detection device comprises a base plate, a vibratingportion and a through hole formed in said base plate, and said porousmember covers at least a part of said through hole.
 48. The liquidcontainer according to claim 47, wherein said detection device furthercomprises a groove connecting with said through hole, and said porousmember is disposed on said groove.
 49. The liquid container according toclaim 42, wherein said detection device and said porous member aredisposed on a plane where said liquid supply opening is formed.
 50. Theliquid container according to claim 42, wherein said detection devicecomprises a vibrating section which generates a counter electromotiveforce in accordance with a residual vibration of said vibrating section,and said detection device detects the liquid consumption status inaccordance with said counter electromotive force.
 51. The liquidcontainer according to claim 42, wherein said detection device detectsat least an acoustic impedance of the liquid and detects a liquidconsumption status in accordance with the acoustic impedance.
 52. Theliquid container according to claim 42, wherein the liquid container ismounted on an ink-jet printing apparatus having a printhead which ejectsink droplets, and the liquid container supplies the liquid containedtherein to the printhead through said liquid supply opening.